The ultimate Oreo cake! Triple layer chocolate cake, cookies and cream filling, chocolate fudge frosting, and white chocolate glaze. Then garnished with more chocolate frosting Oreo cookies.
Make the Cake: Preheat oven to 350 degrees F. Grease three 8-inch round cake pans, line the bottoms with rounds of parchment paper, grease the parchment, then flour the insides of the pans, tapping out excess; set aside.
In the bowl of an electric mixer (or large mixing bowl if you're using a hand mixer), sift together the flour, sugar, cocoa powder, baking soda, baking powder and salt. In a medium bowl, whisk together the eggs, buttermilk, coffee, oil and vanilla.
Add the wet ingredients to the dry ingredients and mix for 2 minutes on medium speed. Scrape the sides and bottom of the bowl and mix for an additional 20 seconds (the batter will be very thin).
Divide the batter evenly among prepared pans. Bake for 20 minutes and rotate the pans in the oven. Continue to bake until a toothpick inserted into the center of one of the cakes comes out almost clean (with a few moist crumbs), about 12 more minutes. Cool the cakes (in the pans) on wire racks for 20 minutes, then carefully turn them out onto cooling racks to cool completely.
Make the Cookies and Cream Filling: Using an electric mixer on medium speed, beat the cream cheese, butter, and vanilla until smooth, about 2 to 3 minutes. Reduce the mixer speed to low and add the powdered sugar, mixing until completely incorporated. Increase the mixer speed to medium-high and beat until fluffy, about 1 minute. Using a rubber spatula, fold in the crushed cookies.
Make the Chocolate Fudge Frosting: Place all ingredients in a food processor and process until smooth, about 1 minute, stopping to scrape the sides of the bowl halfway through.
Make the White Chocolate Glaze: In a large bowl, whisk together the powdered sugar, milk, and vanilla extract until incorporated and smooth. Slowly stir in the white chocolate with a rubber spatula. The glaze should be thick yet pourable; if the glaze appears too thick, thin it out with addition milk, a tablespoon at a time, until you reach the desired consistency.
Assemble the Cake: Place one of the cake layers on a serving platter and spread with half of the cookies and cream filling. Top with another cake layer and spread with the remaining cookies and cream filling. Top with the remaining cake layer. Frost the entire cake with the chocolate fudge frosting. Pour the white chocolate glaze onto the center of the top of the cake and allow to spread and drip over the sides. Refrigerate for at least 15 minutes, or until it is completely set. Using the chocolate fudge frosting, pipe swirls on top of the cake and garnish with additional Oreo cookies. The cake can be kept at room temperature if being served the same day. If you are making the cake ahead of time (or have leftovers), store it in the refrigerator but allow it to sit at room temperature for at least 1 hour prior to serving.
Notes
Pans - I use these 8-inch round pans. You can substitute 9-inch cake pans, but will need to reduce the baking time. Rotate the pans after 15 minutes, then start checking for doneness after 10 additional minutes.
Buttermilk - I highly recommend it for this recipe, but if you are unable to get it, use this substitution: Add 1½ tablespoons of lemon juice or white vinegar to a 2-cup measuring cup, then add enough milk to make 1½ cups. Stir together, then use as directed in the recipe.
Coffee - If you are concerned about the caffeine in the coffee, you can substitute decaf coffee. If you cannot consume coffee, substitute hot water.
Frosting - I make the chocolate fudge frosting in a food processor; see the post above for instructions on using a mixer.
Piping Tip - I use a Wilton 1M piping tip for decorating the top of the cake.
Storage - If the cake will be kept out for longer than one day, it should be refrigerated, covered for up to 1 week. Allow it to sit at room temperature for at least 1 hour before serving.
Freezing - Freeze the entire cake by wrapping in plastic wrap and aluminum foil and freezing for up to 3 months. Thaw overnight in the refrigerator. Freeze individual slices by wrapping in plastic wrap and placing in a ziploc bag. Thaw on the counter for 30 minutes.