Devils food cake is a rich, moist chocolate cake made with dark, unsweetened cocoa powder or chocolate and extra fat - butter or oil - which gives it a deeper chocolate flavor and denser, more tender crumb than a standard chocolate cake. The name's origin is unclear, though it likely emerged in the early 20th-century United States as a decadent counterpart to the airy "angel food cake."
The batter is made much like other chocolate cakes: creaming butter and sugar before adding eggs, flour, baking powder, and cocoa or melted chocolate; some recipes add coffee or espresso powder to deepen the flavor. It's commonly baked as a layer cake and frosted with buttercream, ganache, or cream cheese frosting.