Whether or not a baking tray needs to be greased depends on the recipe and the type of baking tray you are using. Those who cook with silicone baking liners or parchment paper, for example, do not need to grease their baking trays, because the food never comes into contact with a surface it can adhere to. When baking, it is important to understand when a baking tray needs to be greased and what products should be used to grease the pan correctly.
Check the recipe to determine if it is necessary to grease the baking tray. Most recipes will specify whether the sheet should be greased or left ungreased. If no specification is given, check the ingredients. Cookies with large amounts of butter, such as sugar cookies, do not need to be baked on a greased baking tray.
Use unsalted butter, vegetable shortening or cooking spray to grease the bottom of the baking tray. Never use cooking oil, as it will burn in the areas between the cookies and will be very difficult to remove.
Spray cooking spray evenly along the bottom of the baking tray, or use a clean paper towel to spread a thin layer of shortening or butter on the baking tray.
Lightly flour the greased baking tray to prevent chocolate chips from burning when they come into contact with the hot baking surface. A floured surface will also help prevent cookies from spreading and thinning out too much during baking.