Ultimate Peanut Butter Chocolate Cake Recipe

Prepare and preheat

Position an oven rack in the center and preheat oven to 350°F (175°C). Grease and flour two 8-inch round cake pans (or line with parchment) or use a 9x13 pan for a single layer; set aside.

Whisk dry ingredients: In a large bowl, sift or whisk together 2 cups all-purpose flour, 1 1/2 cups granulated sugar, 3/4 cup unsweetened cocoa powder, 1 tsp baking powder, 1 tsp baking soda, and 1/2 tsp salt until evenly combined.

Combine wet ingredients: In a separate bowl, whisk 2 large eggs, 1 cup whole milk, 1/2 cup vegetable oil, and 2 tsp vanilla extract until smooth.

Mix wet into dry: Pour the wet mixture into the dry ingredients and stir until mostly combined and no large dry streaks remain. The batter will be thick.

Add hot liquid: Gradually stir in 1 cup hot water or hot brewed coffee (coffee deepens chocolate flavor). Mix until batter is smooth and pourable. Scrape the bowl to incorporate all flour.

Divide and bake: Divide batter evenly between the prepared pans (about 2 cups batter per 8-inch pan). Smooth the tops. Bake in preheated oven for 25–30 minutes, or until a toothpick inserted into the center comes out with a few moist crumbs. For a 9x13 pan, bake 30–35 minutes.

Cool: Remove cakes from oven and let pans rest on a wire rack for 10 minutes. Run a knife around edges, invert onto racks, remove parchment, and let cool completely before assembly (about 1 hour).

Make peanut butter swirl: In a medium bowl, beat together 1 cup creamy peanut butter, 1/2 cup powdered sugar, 2 tbsp softened unsalted butter, and 1/4 tsp salt until smooth and spreadable. If too stiff, add 1 tsp milk at a time until spreadable; if too soft, add a little more powdered sugar.

Swirl into batter (alternative for single-pan method): If making a single-layer cake or cupcakes, dollop spoonfuls of the peanut butter mixture into the batter and swirl with a knife before baking. For layered cakes proceed to assemble and swirl between layers as directed below.

Heat cream: Place 3/4 cup heavy cream in a small saucepan and warm over medium heat until it just begins to simmer; do not boil. Alternatively microwave in 30-second bursts until steaming.

Combine with chocolate: Place 8 oz chopped chocolate in a heatproof bowl. Pour the hot cream over the chocolate and let sit for 2 minutes. Gently stir until smooth and glossy. Stir in 1 tbsp butter if using for extra shine. Let the ganache cool to a thick, spreadable consistency (15–30 minutes), stirring occasionally.

Level layers: If necessary, level the cooled cake layers with a serrated knife so they stack evenly.

First layer: Place one cake layer on a cake board or serving plate. Spread a thin layer (crumb coat) of peanut butter frosting or a spoonful of ganache to help the swirl adhere.

Add peanut butter swirl: Spoon half of the peanut butter swirl mixture onto the first layer and gently spread to an even layer, leaving a small edge of cake exposed so the peanut butter doesn’t ooze out when stacked.

Add ganache: Spoon a few tablespoons of cooled ganache over the peanut butter layer and spread lightly — this creates a chocolate ribbon between peanut butter layers.

Stack second layer: Place the second cake layer on top and press gently to adhere. If using a third layer, repeat the peanut butter and ganache steps between each layer.

Crumb coat (optional): Use a thin layer of peanut butter frosting (see below) to cover the entire cake to lock in crumbs. Chill 15–20 minutes to set the crumb coat.

Final frost: Spread the remaining peanut butter frosting evenly over the top and sides of the cake using an offset spatula. If you prefer less frosting, simply frost the top and leave the sides naked.

Drizzle ganache: Spoon slightly cooled, pourable ganache over the top edge and allow it to drip down the sides, or pour into the center and spread. For a thicker drizzle, let ganache cool further before using.

Decorate: Sprinkle chopped roasted peanuts, mini chocolate chips, and a tiny pinch of coarse sea salt over the top while ganache is still tacky so they adhere.

Chill and set: Refrigerate the cake 20–30 minutes to allow ganache and frosting to set. If chilled, bring to room temperature 30 minutes before serving for best texture.

Make frosting: In a large bowl, beat 1/2 cup softened unsalted butter until light. Add 1 cup creamy peanut butter and beat until combined. Gradually add 2 1/2 cups powdered sugar, beating on low until incorporated, then increase speed. Add 2 tbsp heavy cream (or milk), 1 tsp vanilla extract, and 1/4 tsp salt. Beat until smooth and spreadable. Adjust consistency with additional cream (to loosen) or powdered sugar (to thicken).

Serve: Slice with a sharp knife wiped between cuts for clean slices. Serve at room temperature or slightly chilled.

Store: Wrap leftover cake or store in an airtight container in the refrigerator for up to 5 days. Bring to room temperature before serving. The cake may also be frozen (well-wrapped) for up to 2 months; thaw overnight in the refrigerator.