Mousse cake is a type of cake that incorporates a light and airy mousse filling. The mousse can be sweet or savory, and is typically made with whipped egg whites, whipped cream, or both, and flavored with chocolate, coffee, caramel, puréed fruits, or various herbs and spices, such as mint or vanilla. Sweetened mousse is served as a dessert or used as an airy cake filling, and can be stabilized with gelatin.

Chocolate mousse cake is a popular variation of mousse cake that combines layers of moist chocolate cake with a creamy chocolate mousse filling. The cake can be covered with a rich chocolate ganache and topped with chocolate whipped cream. Chocolate mousse cake is often served as a dessert and is a favorite among chocolate lovers.