Should You Rotate Cookie Sheets While Baking?

Some cookie recipes include instructions to rotate the baking pans from front to back and between racks partway through baking to promote even browning. Is that necessary? Chowhounds say it depends on how evenly your oven heats, and whether you have a convection feature. Luckily, you can determine if an oven has hot spots without sacrificing cookies: Just bake some sliced bread first.

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