Calling all chocoholics: This Oreo cake boasts cocoa and dark chocolate in the batter plus a cream cheese frosting that's speckled with crushed Oreos. We'll learn how to bake a rich layer cake that's ultra fluffy (thanks to plain yogurt), as well as, how to frost and decorate with piped rosettes.
For the cake: Preheat the oven to 350 degrees F. Butter three 6-inch round cake pans or springform pans then line the bottoms with parchment.
In a medium bowl, combine the flour, cocoa powder, baking powder, baking soda and salt. Gently mix using a spoon.
Beat the 1 1/2 sticks butter and the granulated sugar with an electric mixer on medium speed in a alarge bowl until light and fluffy.
Add the eggs and vanilla and beat on high speed until incorporated. (High speed will prevent this mixture from separating.)
Add the yogurt and melted chocolate and mix on medium-high speed quickly until incorporated.
Add the dry ingredients to the wet ingredients and fold in with a rubber spatula until no streaks of flour remain.
Divide the batter equally among the 3 prepared pans. Bake until a toothpick inserted in the center comes out clean, 22 to 25 minutes.
Loosely cover the pans with foil and let them cool completely on wire racks. Remove the cakes from the pans and peel off the parchment.
For the frosting: Beat the cream cheese and butter with an electric mixer on medium-high speed in a large bowl until smooth. With the machine running, slowly add the confectioners' sugar one spoonful at a time until the frosting is smooth and creamy (do not overbeat). Stir in the vanilla and Oreo crumbs. Refrigerate until needed.
When the cakes are cool, trim off the domed tops with a serrated knife to make the cakes level.
Place one cake trimmed-side down on a cake stand or platter. Spread a spoonful of frosting on top in an even layer. Top with the second cake, trimmed-side up and spread another layer of frosting on top. Repeat with the third cake, trimmed-side down, and some more frosting.
Once all the cake layers are stacked, spread a thin layer of the frosting over the top and sides of the cake with an offset spatula. (This is the crumb coat.) Refrigerate until chilled, at least 30 minutes.
Cover the cake with more frosting, reserving some of the frosting for decorating the top. Frost the cake as evenly as possible. Sprinkle some of the remaining Oreo crumbs over the top of the cake. Transfer the reserved frosting to a pastry bag with a medium round tip. Pipe rosettes around the rim of the cheesecake then top each rosette with a mini Oreo. Enjoy right away or refrigerate for up to 3 days.