Have you ever been shocked by a sudden bang in your oven—and peered in to find that your baking sheet has suddenly seized into a warped position?
Thankfully, this isn’t cause for alarm.
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Why Do Baking Sheets Warp?
Any baking sheet can warp at least a little. It is the natural result of the metal expanding and contracting unevenly across the pan as it heats during cooking and then cools down.
Most pans will spring back into place when the hotter and cooler spots equalize, but they can remain warped if the thermal stress is too great.
A warped pan will still do its job, but we prefer one that sits flat. Your best bet is prevention.
The Cook's Illustrated Baking BookOur popular all-in-one baking book is now in full color! The Cook’s Illustrated Baking Book has it all—definitive recipes for all your favorite cookies, cakes, pies, tarts, breads, pizza, and more, along with kitchen-tested techniques that will transform your baking.
How to Prevent Baking Sheets From Warping
- Avoid rinsing a hot baking sheet in cold water. Instead, let the sheet cool before washing so that the metal can contract gently and evenly in the process.
- Ensure that the food covers the entire pan. Any bare spots will heat faster, and the temperature differential can cause the pan to buckle. If the food won’t cover the pan, switch to a smaller baking sheet.
- Buy a sturdy brand. Our winner is the Nordic Ware Naturals Bakers Half Sheet. For smaller tasks, we love this brand’s quarter-sheet and eighth-sheet versions.
If your sheet still warps, read on.
How To Fix A Warped Baking Sheet
While the following may seem extreme, stick with me. It works.
1. Heat the baking sheet in a 200-degree oven for about 10 minutes, or until warm to the touch.
2. Lay a towel down on a hard and flat surface, such as concrete floor or workbench.
3. Place the pan upside down on the towel.
4. Cover the pan with another towel to prevent scratching, then tap gently with a mallet until the original shape returns. Voila!