How to Choose the Best Cookie Sheet
Shiny aluminum or stainless steel cookie sheets result in delicate, evenly browned cookies.
Insulated cookie sheets give you cookies that may not brown as much on the bottom and may cause some cookie doughs to spread.
Non-stick cookie sheets make cookies easy to remove but the dark finish may cause your cookies to brown more quickly. Many manufacturers suggest lowering the oven temperature by 25 degrees.
Dark aluminum sheets have an almost black finish that may absorb heat and cause the bottoms of your cookies to brown more quickly. You may have to lower the temperature and bake for a shorter time.