Chocolate Cake with Oreo Buttercream Frosting Recipe

Preheat oven to 350°F. Grease and flour 2 (6-inch) round cake pans. Sift together flour, cocoa powder, baking soda, and salt into a bowl. Set aside.

In the bowl of an electric mixer fitted with the paddle attachment, cream butter and sugar on medium speed until light and fluffy. Beat in eggs one at a time. Stir in vanilla.

Beat in flour mixture alternately with milk on low speed, mixing just until incorporated. Divide batter evenly between pans.

Bake in the preheated oven for 40 to 45 minutes or until a toothpick inserted in the center of each cake comes out clean. Allow to cool completely in pans before unmolding.

Make the Oreo buttercream: Lightly whisk egg whites and sugar together in a bowl over a pot of simmering water until hot to the touch and all sugar granules have melted (about 140ºF). Transfer mixture to the bowl of an electric mixer fitted with the whisk attachment. Whip on medium-high speed until stiff and mixture doubles in volume. (The whites should be cool to the touch.)

Add butter, a few cubes at a time, while beating. (When all of the butter cubes are mixed in, the mixture should be light and fluffy.) Mix in crushed Oreos. (If buttercream starts to loosen and melt, chill it first before using to frost the cake, but make sure it doesn't set or get too stiff.)

Using a serrated knife, carefully slice off tops of each cake to make a flat surface; reserve tops. Slice each cake layer in half horizontally to make 4 equal layers. Place a layer on a cake plate or cake stand. Spread about 2/3 cup of the Oreo buttercream evenly on top then cover with the second layer. Repeat until the four layers are stacked. Chill cake for about 30 minutes before frosting completely with the rest of the buttercream. Chill for another 30 minutes.

Place reserved cake tops in a food processor; pulse until fine. Use crumbs to decorate the base and top of the cake. Decorate top with Oreo cookies, Pepero sticks, Ferrero Rocher balls, and chocolate truffles.