Shiny aluminum The best choice for cookies that are consistent in color, shape and size. It prevents cookies from becoming too dark on the bottom.

Dark nonstick These sheets help keep your cookies from sticking. However, they tend to brown cookies quickly, particularly on the bottom. Also, the dark color makes cookies bake faster, so they may not spread as much as desired. Many nonstick baking pan manufacturers recommend reducing the oven temperature by 25°F.

Insulated Consists of two thin sheets of aluminum with a layer of air between them. Desirable for lighter-colored, soft cookies. Cookies baked on insulated cookie sheets may require more baking time. Cookies may also be more likely to stick.

For more even baking, use cookie sheets without rims. Also, cookies baked on cookie sheets without rims will be crisper.

Cookie sheets with rims can be turned over; the cookie dough is then placed on the underside of the sheet and baked according to recipe directions.

For best results, use cookie sheets or baking pans that leave at least 2 inches between the sheet/pan and the oven sides, back and door. This allows air to circulate and heat to be evenly distributed in the oven.

Cookie sheets need to cool completely between batches, or cookies may spread too much.