A 6 inch round flan foil is a type of kitchen tool used to make and bake flan, a type of dessert that is similar to a custard. The foil is typically made of a lightweight, aluminum material and is used to mold and shape the flan mixture before baking. The round shape and 6-inch diameter of the foil is designed to fit a small size flan dish. This size is perfect for making individual servings of flan or small flans for parties.