Pipe a 1/2-inch-tall border of icing around edge of first cake layer. Spoon half of chocolate mousse (about 2 cups) onto center of cake, and spread evenly within border using a small offset spatula.
Get the recipe: The Best Chocolate Cake Recipe {Ever} Preheat the oven to 350ºF. Prepare two nine-inch cake pans by coating them with baking spray, or buttering and lightly flouring them.
Distribute the cake batter evenly between the two prepared cake pans. Bake the cakes for 30 to 35 minutes, or until a toothpick inserted in the center of the chocolate cake comes out clean. Take the ...