A type of icing or filling, used inside cakes, as a coating, and as decoration. In its simplest form, it is made by creaming butter with powdered sugar, although other fats can be used, such as margarine or lard. Colorings and flavourings are often added, such as cocoa powder or vanilla extract. Buttercreams are a popular topping for cupcakes, sponge cakes, butter cakes and other desserts.