Butter cream or buttercream or mock cream is a type of icing used inside cakes, as a coating, and as decoration. In its simplest form, it is made by creaming butter with icing sugar, although other fats can be used, such as margarine. Colorings and flavorings are often added, such as cocoa powder or vanilla extract.

Buttercreams are the most common frosting used in American bakeries, ranging in sweetness depending on the type. A notable use of buttercream is in butterfly cakes, although it is popular as a topping for many other forms of Victoria sponge.