Permissible ways to heat up food on Shabbat: Difference between revisions

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# If one lacks either of the last two requirements (intent, being held), one may return a pot of food to the fire even as long as the food is needed and the other four requirements are satisfied. <ref> Shemirat Shabbat KeHilchata 1:19 </ref>
# If one lacks either of the last two requirements (intent, being held), one may return a pot of food to the fire even as long as the food is needed and the other four requirements are satisfied. <ref> Shemirat Shabbat KeHilchata 1:19 </ref>
# If one lacks both of the last two requirements (intent, being held), one may return the pot to the fire only if one will not have hot food on Shabbat if one doesn't return it to the fire. <ref> Shemirat Shabbat KeHilchata 1:20 </ref>
# If one lacks both of the last two requirements (intent, being held), one may return the pot to the fire only if one will not have hot food on Shabbat if one doesn't return it to the fire. <ref> Shemirat Shabbat KeHilchata 1:20 </ref>
==Basics==
# There’s a rabbinic prohibition in returning cooked foods to a fire on Shabbat because it looks like cooking. <Ref> Baal HaMoar 16b, Rashba (38b D”H MeKlal) in name of some geonim, Ritva (40b D”H VeAskina), and Ran (17b D”H Bei Rav Ashi) write that the prohibition of Chazara is a gezerah of Chazal because it looks like cooking when one heats up cold food on Shabbat. </ref>
==Chazara to the fire or a Kli Rishon==
#
# On Shabbat some posikim permit one to cover the fire with a metal tray if the flame isn’t strong enough to make the tray red-hot. <Ref> Sh”t Zera Emet 3:26 permits one to put a metal tray (with small holes) on a fire on Shabbat and then do Chazara based on S”A 318:8 where he brings the dispute whether one can do Chazara on an empty over the fire and rules like the lenient opinion. Chazon Ish 37:11 argues that actually placing the metal sheet on the fire is the forbidden act of [[Mavir]] based on Rambam (Shabbat 12:1, 9:6) who says that one who heats metal to mold it violates [[Mavir]]. Even though S”A 253:3 writes that on Shabbat day one can put a empty pot on a fire (and then return a pot that was on the fire right before), Chazon Ish explains that S”A is talking about a earthenware pot and not metal. However Nishmat Adam 20:1, Kesot HaShulchan (134 pg 42), Sh”t Shevet Halevi 1:91, Sh”t She’ilat Shaul 29, Chazon Ovadyah (Shabbat 1 pg 55), and Sh”t Tefilah LeMoshe 1:59 (pg 647) argue that in our case the tray won’t become hot as a coal or hot enough to be reshaped and so it should be permitted. So rules Shemirat Shabbat KeHilchata 1:38 to permit covering the fire as long as the fire isn’t strong enough to make the tray red-hot. </ref>
# One may not return food to the oven on Shabbat even if the food is fully cooked and is very hot since an oven is considered an uncovered flame, chazara is forbidden. <Ref>Shemirat Shabbat KeHilchata 1:17 </ref>
# If there’s a metal box insert in the oven, some consider the fire to be a covered one. <Ref> Sh”t Igrot Moshe 4:74:27 permits returning food to an oven on Shabbat if the oven has a metal insert of 4 sides to serve as a reminder. However, Sh”t Shevet HaLevi 3:48 argues on Igrot Moshe and holds that under all circumstances it’s forbidden to return food to the inside of an oven. </ref>
==Conditions to permit Chazara==
# Someone who takes food off the fire on Shabbat may return it under the following conditions:
*1) the food is fully cooked  <ref> S”A 318:4 and Rama 253:2 rule like the Rambam and Tur who hold that unless foods are fully cooked one would violate Bishul Deoritta, against the Rosh (Shabbat 3:10-11) and Rashba (Shabbat 18b) who hold that once food is cooked KeMachal Ben Dursai it’s permissible to cook it even until it’s fully cooked food. Therefore, one may not return to the fire any food that’s not fully cooked otherwise there’s a potential Deoritta violation of bishul. Accordingly, Biur Halacha 318:4 D”H Shayach writes that even if one is in doubt whether the food is fully cooked or not one may not return the food to the fire. So brings Shemirat Shabbat KeHilchata 3:18 note 55. </ref>
*2) the fire must be covered <ref> S”A 253:2 writes that one may return hot food if the fire is Garuf or Katum. Mishna Brurah 253:81 adds that a similar metal try can be used as a cover of the fire to separate the fir from the pot. Similarly, S”A 253:3 writes that if on Shabbat morning one finds the food in one’s pot burning, one may remove it from the fire, put an empty pot on the fire and then the pot with food in it on top of the empty pot. Mishna Brurah 253:81 comments that it’s permissible to put the pot back on the fire since there’s an empty pot on the fire making it like Garuf or Katum. Kaf HaChaim 253:11, Sh”t Maharshag 2:50, Sh”t Igrot Moshe 1:93, and Shemirat Shabbat KeHilchata 1:18 rule that the fire must be covered in order to do chazara (Shemirat Shabbat KeHilchata (1 note 54 quotes Rabbi Shlomo Zalman as saying that one shouldn’t increase the flame when one puts a cover on top of it). Many poskim including Mishna Brurah 318:91, Shemirat Shabbat KeHilchata (chapter 1 note 59) in name of Rav Shlomo Zalman, and Sh”t Igrot Moshe 1:93 rule that one may cover the fire on Shabbat even if the pot is metal against Chazon Ish 37:11 who forbids putting metal on fire where it’ll become 113 degrees. </ref>
*3) at the time it was removed from the fire, one intends to put it back <ref> Rama 253:2 in name of the Tur rules that one must have intention to return the food to the fire when one takes it off. So rules Shemirat Shabbat KeHilchata 1:18. Mishna Brurah 253:56 writes that if one still has the food in one’s hand but didn’t intend to return it to fire, one can be lenient in cases of need. </ref>
*4) According to Ashkenazim, the pot must remain in one’s hand or in one’s hand while resting on a table or ground, however according to Sephardim, as long as the pot wasn’t placed on the ground, one may return it. <ref> Rama 253:2 writes that one of the conditions of chazara is that one keeps the pot in one’s hand. Mishna Brurah 253:55 writes that it’s forbidden to return the pot even if one put it down on a table or bench. However, writes the Shemirat Shabbat KeHilchata 1:18, if one keeps one hand on the pot as one rests in on a table one may return the pot to the covered fire. So rules the Torat Shabbat 253:11, Demesk Eliezer 253:11, Sh”t Igrot Moshe 4:74:33, and the 39 Melachot (vol 2 pg 619, by Rabbi Ribiat) rule that as one as one keeps one’s hand on the pot even if the pot was rested on a table or bench one may return the pot. [However, from the Biur Halacha 253:2 D”H Velo it seems not like this.] On the other hand, S”A 253:2 writes that one of the conditions is to make sure not to place the pot on the ground. Magan Avraham 253:20 writes that the S”A argues on the Rama and permits leaving it on a table or bench if one intends to return it to the fire. So rules Yalkut Yosef (Shabbat vol 1 pg 103) that there’s no requirement to have the food in hand. </ref>
*5) According to Ashkenazim, the food (liquid and solid) should be slightly warm in order to return it to the fire, however some argue that solids don’t need to be warm at all. On the other hand, according to Sephardim, the liquids must still be 113 degrees (and solids can be cold). <ref> S”A 253:2 writes that a condition of chazara is that the food is still boiling meaning that it’s 113 degrees. This condition is referring specifically to liquids as the Mishna Brurah 253:54 explains that this condition is dependant one of bishul and not chazara. Since S”A 318:4 rules that a liquid may not be heated up once it’s not 113 degrees, so too here a liquid may not be put back on the covered fire unless it’s 113 degrees. However, Rama 253:2 and 318:15 writes that Ashkenazim are lenient to allow returning a fully cooked liquid as long as it’s now slightly warm. So holds Mishna Brurah 253:54 and Shemirat Shabbat KeHilchata 1:18. Regarding solids, the Magan Avraham 253:36 writes that it also must be somewhat warm in order to return it to the fire. However, the Biur Halacha 253:5 D”H Ubilvad argues on the Magan Avraham based on the Buir HaGra. [It seems that Mishna Brurah 253:54, 91 rules like the Gra against the Magan Avraham even though he quotes the Magan Avraham (in 253:68).] The Shemirat Shabbat KeHilchata 1:18 seems to rule like the Magan Avraham however, it’s unclear what he holds based on the footnote. Yalkut Yosef (Shabbat vol 1 pg 103), and Menuchat Ahava (3:2, vol 1 pg 50) agree with the Biur Halacha that one may be lenient. </ref>
==Explanation of the forth criteria==
# According to Ashkenazim, in cases of need one may return food if it was placed on a table or bench as long as one had intent to return it a covered fire. <Ref> Buir Halacha 253:2 D”H VeDato writes in cases where one had intent to return the pot to the fire, and left it on the ground, in a case of need there’s room to be lenient, however, there’s certainly a reason to be lenient. So rules Shemirat Shabbat KeHilchata 1:19, Orchot Shabbat (vol 1 pg 85; seemingly the orchot Shabbat quotes Biur Halacha even in cases where there’s no need). </ref>
# Some say that marble countertops are considered like a table or bench and if placed down there without intent, one may return it if there’s a need for the food. However, others say that marble countertops are considered like the ground and one shouldn’t return it to the fire unless there’s no other hot food. <Ref> Regarding placing a pot on a marble countertop there’s a dispute in the poskim. Petach Dvir 253:2, Sh”t Yitzchak Yiranen 2:42, and Menuchat Ahava 3:2, 3:8(3) write that anything attached to the ground is considered like the ground. Yalkut Yosef (Shabbat vol 1 pg 193 note 9) says that one has what to rely on if it was left on marble and not on the ground itself. Orchot Shabbat 2:46 brings a dispute between Rav Elyashiv, Rav Shlomo Zalman, and Rav Nassim Karlitz who are lenient regarding marble counters while, Rav Wosner is strict on this issue. </ref>
==If some of the conditions are lacking==
# If the pot was placed on a table or chair (and let go) but one had intent to return it to the fire, or one still has it in one’s hand but didn’t have intent to return it to the fire, one may be lenient if the food is needed as long as the other requirements (covered fire, fully cooked, still warm) have not been breached. <Ref> Buir Halacha 253:2 D”H VeDato (and Mishna Brurah 253:56) writes that if necessary (Shat Tzorech) one can rely on the Rishonim who say one doesn’t need intent if it’s still in one’s hand or one doesn’t need it in one’s hands if one has intent. So rules Shemirat Shabbat KeHilchata 1:19</ref>
# If one didn’t have intent to return the pot to the fire and the pot was placed on a table or chair (and let go), one shouldn’t be lenient to eat the food unless there’s no other hot food. <Ref>Shemirat Shabbat KeHilchata 1:20 </ref>
==Moving from one fire to another==
# It’s permissible to move a pot from a small fire to a larger one, which is properly covered. <Ref>Shemirat Shabbat KeHilchata 1:21 </ref>
# A pot was on the edge of the blech (not above the fire) may be moved to the center of the blech (above the fire) as long as the area where the pot was originally was as hot as 113 degrees and the food was fully cooked. <Ref> Shemirat Shabbat KeHilchata 1:22 </ref>
==With what foods can Chazara be permitted?==
#
==Chazara on a Blech==
# Many poskim permit Chazara on a plaata. <Ref> Chazon Ovadyah (Shabbat 1 pg 55) holds that since Chazara is only forbidden as it looks like cooking a plaata which isn’t used for cooking should be permitted for Chazara. Rav Frankel (Kol Torah (Iyar 5723, Sh”t Har Tzvi O”C 136, Toldot Zev (Shabbat 2 pg 234)) concurs. Sh”t Igrot Moshe (O”C 4:74(35), 1:93) permits Chazara on a blech if the food is fully cooked because it’s not used to cook and being a blech for Shabbat it serves as a reminder it’s Shabbat. Sh”t Yashkil LeAvdi O”C 7:28, Rav Shlomo Zalman Aurbach (Shulchan Shlomo 253:27), Sh”t Tzitz Eliezer 8:26, Chukei Chaim Peretz 8 in name of Rav Sheinberg, Sh”t Me’oneh Lashon 22, Sh”t Shemesh UMagen (3:54(3) in retraction of his stringent opinion in 1:53), Sh”T Tefilah LeMoshe 1:32, and Yitzchak Yiranen (pg 50) concur to permit Chazara on a plaata and so is the Minhag. However, Yashiv Moshe (Rabbi Twersky pg 36) in name of Rav Elyashiv, and Sh”t Avnei Yishfeh 1:83 are strict because a plaata is sometimes used to cook. </ref>




==References==
==References==
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<references/>

Revision as of 03:09, 4 April 2011

  1. According to Ashkenazim, a pot of food, which was taken from the fire, one may not be returned to the fire unless it fulfills the following conditions.
  • the fire is covered (with something that upon which one wouldn't cook during the week like a blech),
  • the food is fully cooked,
  • the food has not completely cooled off,
  • the pot was taken with intent to be put back, and
  • the pot is being held (and may be placed on a dry area except the floor while being held). [1]

Clarifying the first requirement

  1. One may not return the inset of a crockpot to the base unless it was covered with aluminum foil (or the like) and it's preferable to cover the knob as well. [2]

If one lacks the last two requirement

  1. If one lacks either of the last two requirements (intent, being held), one may return a pot of food to the fire even as long as the food is needed and the other four requirements are satisfied. [3]
  2. If one lacks both of the last two requirements (intent, being held), one may return the pot to the fire only if one will not have hot food on Shabbat if one doesn't return it to the fire. [4]


Basics

  1. There’s a rabbinic prohibition in returning cooked foods to a fire on Shabbat because it looks like cooking. [5]

Chazara to the fire or a Kli Rishon

  1. On Shabbat some posikim permit one to cover the fire with a metal tray if the flame isn’t strong enough to make the tray red-hot. [6]
  2. One may not return food to the oven on Shabbat even if the food is fully cooked and is very hot since an oven is considered an uncovered flame, chazara is forbidden. [7]
  3. If there’s a metal box insert in the oven, some consider the fire to be a covered one. [8]

Conditions to permit Chazara

  1. Someone who takes food off the fire on Shabbat may return it under the following conditions:
  • 1) the food is fully cooked [9]
  • 2) the fire must be covered [10]
  • 3) at the time it was removed from the fire, one intends to put it back [11]
  • 4) According to Ashkenazim, the pot must remain in one’s hand or in one’s hand while resting on a table or ground, however according to Sephardim, as long as the pot wasn’t placed on the ground, one may return it. [12]
  • 5) According to Ashkenazim, the food (liquid and solid) should be slightly warm in order to return it to the fire, however some argue that solids don’t need to be warm at all. On the other hand, according to Sephardim, the liquids must still be 113 degrees (and solids can be cold). [13]

Explanation of the forth criteria

  1. According to Ashkenazim, in cases of need one may return food if it was placed on a table or bench as long as one had intent to return it a covered fire. [14]
  2. Some say that marble countertops are considered like a table or bench and if placed down there without intent, one may return it if there’s a need for the food. However, others say that marble countertops are considered like the ground and one shouldn’t return it to the fire unless there’s no other hot food. [15]

If some of the conditions are lacking

  1. If the pot was placed on a table or chair (and let go) but one had intent to return it to the fire, or one still has it in one’s hand but didn’t have intent to return it to the fire, one may be lenient if the food is needed as long as the other requirements (covered fire, fully cooked, still warm) have not been breached. [16]
  2. If one didn’t have intent to return the pot to the fire and the pot was placed on a table or chair (and let go), one shouldn’t be lenient to eat the food unless there’s no other hot food. [17]

Moving from one fire to another

  1. It’s permissible to move a pot from a small fire to a larger one, which is properly covered. [18]
  2. A pot was on the edge of the blech (not above the fire) may be moved to the center of the blech (above the fire) as long as the area where the pot was originally was as hot as 113 degrees and the food was fully cooked. [19]


With what foods can Chazara be permitted?

Chazara on a Blech

  1. Many poskim permit Chazara on a plaata. [20]


References

  1. Shemirat Shabbat KeHilchata 1:18
  2. Shabbat Kitchen pg 60 by Rabbi Simcha Bunim Cohen
  3. Shemirat Shabbat KeHilchata 1:19
  4. Shemirat Shabbat KeHilchata 1:20
  5. Baal HaMoar 16b, Rashba (38b D”H MeKlal) in name of some geonim, Ritva (40b D”H VeAskina), and Ran (17b D”H Bei Rav Ashi) write that the prohibition of Chazara is a gezerah of Chazal because it looks like cooking when one heats up cold food on Shabbat.
  6. Sh”t Zera Emet 3:26 permits one to put a metal tray (with small holes) on a fire on Shabbat and then do Chazara based on S”A 318:8 where he brings the dispute whether one can do Chazara on an empty over the fire and rules like the lenient opinion. Chazon Ish 37:11 argues that actually placing the metal sheet on the fire is the forbidden act of Mavir based on Rambam (Shabbat 12:1, 9:6) who says that one who heats metal to mold it violates Mavir. Even though S”A 253:3 writes that on Shabbat day one can put a empty pot on a fire (and then return a pot that was on the fire right before), Chazon Ish explains that S”A is talking about a earthenware pot and not metal. However Nishmat Adam 20:1, Kesot HaShulchan (134 pg 42), Sh”t Shevet Halevi 1:91, Sh”t She’ilat Shaul 29, Chazon Ovadyah (Shabbat 1 pg 55), and Sh”t Tefilah LeMoshe 1:59 (pg 647) argue that in our case the tray won’t become hot as a coal or hot enough to be reshaped and so it should be permitted. So rules Shemirat Shabbat KeHilchata 1:38 to permit covering the fire as long as the fire isn’t strong enough to make the tray red-hot.
  7. Shemirat Shabbat KeHilchata 1:17
  8. Sh”t Igrot Moshe 4:74:27 permits returning food to an oven on Shabbat if the oven has a metal insert of 4 sides to serve as a reminder. However, Sh”t Shevet HaLevi 3:48 argues on Igrot Moshe and holds that under all circumstances it’s forbidden to return food to the inside of an oven.
  9. S”A 318:4 and Rama 253:2 rule like the Rambam and Tur who hold that unless foods are fully cooked one would violate Bishul Deoritta, against the Rosh (Shabbat 3:10-11) and Rashba (Shabbat 18b) who hold that once food is cooked KeMachal Ben Dursai it’s permissible to cook it even until it’s fully cooked food. Therefore, one may not return to the fire any food that’s not fully cooked otherwise there’s a potential Deoritta violation of bishul. Accordingly, Biur Halacha 318:4 D”H Shayach writes that even if one is in doubt whether the food is fully cooked or not one may not return the food to the fire. So brings Shemirat Shabbat KeHilchata 3:18 note 55.
  10. S”A 253:2 writes that one may return hot food if the fire is Garuf or Katum. Mishna Brurah 253:81 adds that a similar metal try can be used as a cover of the fire to separate the fir from the pot. Similarly, S”A 253:3 writes that if on Shabbat morning one finds the food in one’s pot burning, one may remove it from the fire, put an empty pot on the fire and then the pot with food in it on top of the empty pot. Mishna Brurah 253:81 comments that it’s permissible to put the pot back on the fire since there’s an empty pot on the fire making it like Garuf or Katum. Kaf HaChaim 253:11, Sh”t Maharshag 2:50, Sh”t Igrot Moshe 1:93, and Shemirat Shabbat KeHilchata 1:18 rule that the fire must be covered in order to do chazara (Shemirat Shabbat KeHilchata (1 note 54 quotes Rabbi Shlomo Zalman as saying that one shouldn’t increase the flame when one puts a cover on top of it). Many poskim including Mishna Brurah 318:91, Shemirat Shabbat KeHilchata (chapter 1 note 59) in name of Rav Shlomo Zalman, and Sh”t Igrot Moshe 1:93 rule that one may cover the fire on Shabbat even if the pot is metal against Chazon Ish 37:11 who forbids putting metal on fire where it’ll become 113 degrees.
  11. Rama 253:2 in name of the Tur rules that one must have intention to return the food to the fire when one takes it off. So rules Shemirat Shabbat KeHilchata 1:18. Mishna Brurah 253:56 writes that if one still has the food in one’s hand but didn’t intend to return it to fire, one can be lenient in cases of need.
  12. Rama 253:2 writes that one of the conditions of chazara is that one keeps the pot in one’s hand. Mishna Brurah 253:55 writes that it’s forbidden to return the pot even if one put it down on a table or bench. However, writes the Shemirat Shabbat KeHilchata 1:18, if one keeps one hand on the pot as one rests in on a table one may return the pot to the covered fire. So rules the Torat Shabbat 253:11, Demesk Eliezer 253:11, Sh”t Igrot Moshe 4:74:33, and the 39 Melachot (vol 2 pg 619, by Rabbi Ribiat) rule that as one as one keeps one’s hand on the pot even if the pot was rested on a table or bench one may return the pot. [However, from the Biur Halacha 253:2 D”H Velo it seems not like this.] On the other hand, S”A 253:2 writes that one of the conditions is to make sure not to place the pot on the ground. Magan Avraham 253:20 writes that the S”A argues on the Rama and permits leaving it on a table or bench if one intends to return it to the fire. So rules Yalkut Yosef (Shabbat vol 1 pg 103) that there’s no requirement to have the food in hand.
  13. S”A 253:2 writes that a condition of chazara is that the food is still boiling meaning that it’s 113 degrees. This condition is referring specifically to liquids as the Mishna Brurah 253:54 explains that this condition is dependant one of bishul and not chazara. Since S”A 318:4 rules that a liquid may not be heated up once it’s not 113 degrees, so too here a liquid may not be put back on the covered fire unless it’s 113 degrees. However, Rama 253:2 and 318:15 writes that Ashkenazim are lenient to allow returning a fully cooked liquid as long as it’s now slightly warm. So holds Mishna Brurah 253:54 and Shemirat Shabbat KeHilchata 1:18. Regarding solids, the Magan Avraham 253:36 writes that it also must be somewhat warm in order to return it to the fire. However, the Biur Halacha 253:5 D”H Ubilvad argues on the Magan Avraham based on the Buir HaGra. [It seems that Mishna Brurah 253:54, 91 rules like the Gra against the Magan Avraham even though he quotes the Magan Avraham (in 253:68).] The Shemirat Shabbat KeHilchata 1:18 seems to rule like the Magan Avraham however, it’s unclear what he holds based on the footnote. Yalkut Yosef (Shabbat vol 1 pg 103), and Menuchat Ahava (3:2, vol 1 pg 50) agree with the Biur Halacha that one may be lenient.
  14. Buir Halacha 253:2 D”H VeDato writes in cases where one had intent to return the pot to the fire, and left it on the ground, in a case of need there’s room to be lenient, however, there’s certainly a reason to be lenient. So rules Shemirat Shabbat KeHilchata 1:19, Orchot Shabbat (vol 1 pg 85; seemingly the orchot Shabbat quotes Biur Halacha even in cases where there’s no need).
  15. Regarding placing a pot on a marble countertop there’s a dispute in the poskim. Petach Dvir 253:2, Sh”t Yitzchak Yiranen 2:42, and Menuchat Ahava 3:2, 3:8(3) write that anything attached to the ground is considered like the ground. Yalkut Yosef (Shabbat vol 1 pg 193 note 9) says that one has what to rely on if it was left on marble and not on the ground itself. Orchot Shabbat 2:46 brings a dispute between Rav Elyashiv, Rav Shlomo Zalman, and Rav Nassim Karlitz who are lenient regarding marble counters while, Rav Wosner is strict on this issue.
  16. Buir Halacha 253:2 D”H VeDato (and Mishna Brurah 253:56) writes that if necessary (Shat Tzorech) one can rely on the Rishonim who say one doesn’t need intent if it’s still in one’s hand or one doesn’t need it in one’s hands if one has intent. So rules Shemirat Shabbat KeHilchata 1:19
  17. Shemirat Shabbat KeHilchata 1:20
  18. Shemirat Shabbat KeHilchata 1:21
  19. Shemirat Shabbat KeHilchata 1:22
  20. Chazon Ovadyah (Shabbat 1 pg 55) holds that since Chazara is only forbidden as it looks like cooking a plaata which isn’t used for cooking should be permitted for Chazara. Rav Frankel (Kol Torah (Iyar 5723, Sh”t Har Tzvi O”C 136, Toldot Zev (Shabbat 2 pg 234)) concurs. Sh”t Igrot Moshe (O”C 4:74(35), 1:93) permits Chazara on a blech if the food is fully cooked because it’s not used to cook and being a blech for Shabbat it serves as a reminder it’s Shabbat. Sh”t Yashkil LeAvdi O”C 7:28, Rav Shlomo Zalman Aurbach (Shulchan Shlomo 253:27), Sh”t Tzitz Eliezer 8:26, Chukei Chaim Peretz 8 in name of Rav Sheinberg, Sh”t Me’oneh Lashon 22, Sh”t Shemesh UMagen (3:54(3) in retraction of his stringent opinion in 1:53), Sh”T Tefilah LeMoshe 1:32, and Yitzchak Yiranen (pg 50) concur to permit Chazara on a plaata and so is the Minhag. However, Yashiv Moshe (Rabbi Twersky pg 36) in name of Rav Elyashiv, and Sh”t Avnei Yishfeh 1:83 are strict because a plaata is sometimes used to cook.