To make it easier to remove and cut bar cookies, line the baking pan with foil. Here's a simple tip: Tear off a piece of foil that's large enough to extend over the edges of the pan. Invert the baking pan on the countertop and shape the foil over the baking pan until it fits. Turn the pan upright, then place foil inside, smoothing it to fit inside the pan. If your recipe says to grease the pan, grease the foil lining instead.
Here's a simple tip that allows you to easily remove delicate meringue cookies from the cookie sheet: Line your cookie sheet with parchment paper. Use the food-safe parchment paper instead of brown paper grocery bags because they may contain recycled materials. After baking, transfer the meringue cookies to a wire rack for cooling.
Check cookies for doneness at the minimum baking time called for in the recipe. A kitchen timer is a helpful reminder. When the cookies are done, remove them from the cookie sheet immediately unless directed otherwise in the recipe. Some cookies are left on the cookie sheet for a specified amount of time to let them set.
Use a spatula to transfer hot cookies to a wire rack for even cooling. Wire racks can be easily cleaned. Let the cookies cool completely before storing.