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Decadent Peanut Butter Oreo Cake with chocolate layers and Oreo cookie toppings

Decadent Peanut Butter Oreo Chocolate Delight Cake

A show-stopping dessert combining peanut butter, Oreo cookies, and silky chocolate ganache, perfect for celebrations or comforting evenings.
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Prep Time 30 minutes
Cook Time 50 minutes
Total Time 1 hour 20 minutes
Servings: 10 servings
Course: Cake, Dessert
Cuisine: American
Calories: 500
Ingredients Method Notes

Ingredients
  

For the Oreo peanut-butter crust
  • 2 cups finely crushed Oreo cookies, about 22–24 cookies Filling included
  • 1/3 cup salted butter, melted
  • 2 tbsp creamy peanut butter
For the chocolate cake layer
  • 1 3/4 cups all-purpose flour
  • 3/4 cup unsweetened cocoa powder
  • 1 1/2 tsp baking powder
  • 1 1/2 tsp baking soda
  • 1 tsp salt
  • 2 cups granulated sugar
  • 2 large eggs, room temperature
  • 1 cup whole milk (or milk of choice)
  • 1/2 cup vegetable oil
  • 2 tsp vanilla extract
  • 1 cup boiling water Helps thin the batter
For the peanut butter filling
  • 1 1/2 cups creamy peanut butter (natural or classic)
  • 1 cup powdered sugar, sifted
  • 1/2 cup unsalted butter, softened
  • 3–4 tbsp heavy cream or milk To adjust consistency
For the chocolate ganache
  • 10 oz dark chocolate (60–70% cacao), chopped
  • 1 cup heavy cream
  • 2 tbsp unsalted butter (optional, for shine)
To finish
  • 6–8 pieces mini peanut butter cups, halved
  • 1/2 cup chopped Oreos
  • sea salt flakes (optional) For garnish

Method
 

Preparation
  1. Preheat oven to 350°F (175°C). Grease two 9-inch round pans and line bottoms with parchment.
Make the Oreo peanut-butter crust
  1. Pulse Oreo cookies in a food processor until very fine.
  2. Combine crumbs with melted butter and 2 tbsp peanut butter. Press evenly into the bottom of one lined 9-inch pan.
  3. Bake for 8–10 minutes to set; cool while you make the cake.
Bake the chocolate cake
  1. Whisk flour, cocoa, baking powder, baking soda, salt, and sugar in a large bowl.
  2. In another bowl, combine eggs, milk, oil, and vanilla. Add wet to dry and mix until combined.
  3. Stir in boiling water until batter is smooth (it will be thin).
  4. Divide batter between the two pans or pour over the crust in the pan with the set crust.
  5. Bake for 25–30 minutes, or until a toothpick comes out with a few moist crumbs. Cool in pans for 10 minutes, then transfer to wire racks.
Make the peanut butter filling
  1. Beat softened butter and peanut butter until smooth.
  2. Gradually add powdered sugar, then add cream 1 tablespoon at a time until spreadable consistency is achieved.
  3. Taste and adjust salt or sweetness as needed.
Make the chocolate ganache
  1. Place chopped chocolate in a heat-proof bowl.
  2. Heat cream until just simmering, pour over chocolate, and let sit for 2 minutes.
  3. Stir until glossy and smooth, then stir in butter.
  4. Let ganache cool until slightly thickened but still pourable.
Assemble the cake
  1. If you baked two cake layers separately, level tops if necessary.
  2. Place one chocolate cake layer on a cake plate and spread half the peanut butter filling evenly.
  3. Add the second cake layer, then spread the remaining filling on top.
  4. Pour ganache over the top, letting it drip down the sides. Sprinkle chopped Oreos and halved peanut butter cups.
  5. Finish with a light dusting of sea salt if desired.
Chill and serve
  1. Chill the cake for 30–60 minutes so the ganache sets, then slice with a hot, clean knife.
  2. Keep refrigerated for up to 4 days; bring slices to room temperature before serving for best texture.

Notes

For a lighter peanut butter flavor, reduce the peanut butter in the filling by 1/4 cup. For extra peanut-buttery flavor, add chopped cups into the filling for texture. Store leftovers covered in the fridge for up to 4 days.