Peanut Butter Chocolate Cake

Why You’ll Love This Recipe

• Moist, tender chocolate cake made extra chocolatey with hot coffee to bloom the cocoa.
• Rich, fluffy peanut butter buttercream that spreads like a dream without being overly sweet.
• Glossy chocolate ganache drip for that bakery-style finish at home.
• Crunchy-salty topping (Reese’s or peanuts) that nails the classic chocolate–peanut butter combo.

Grocery List

• Produce: None
• Dairy: Buttermilk, large eggs, unsalted butter, heavy cream
• Pantry: All-purpose flour, granulated sugar, confectioners’ sugar, unsweetened cocoa powder, baking powder, baking soda, fine salt, vegetable oil, vanilla extract, brewed coffee, semi-sweet chocolate, light corn syrup (optional), mini peanut butter cups, roasted salted peanuts, parchment paper

Full Ingredients

Chocolate Cake

• All-purpose flour: 1 3/4 cups (220 g)
• Granulated sugar: 2 cups (400 g)
• Unsweetened cocoa powder (Dutch-process or natural): 3/4 cup (75 g)
• Baking powder: 1 1/2 tsp
• Baking soda: 1 1/2 tsp
• Fine sea salt: 1 tsp
• Large eggs: 2 (room temperature)
• Buttermilk: 1 cup (240 ml), room temperature
• Vegetable oil: 1/2 cup (120 ml)
• Pure vanilla extract: 2 tsp
• Very hot brewed coffee: 1 cup (240 ml)

Peanut Butter Buttercream

• Unsalted butter: 1 1/4 cups (283 g), softened
• Creamy peanut butter (no-stir style): 1 1/2 cups (384 g)
• Confectioners’ sugar: 4 1/2 cups (540 g), sifted
• Fine sea salt: 1/4 tsp (or to taste)
• Pure vanilla extract: 2 tsp
• Heavy cream: 1/3 cup (80 ml), plus 1–2 tbsp more as needed

Chocolate Ganache Drip

• Semi-sweet chocolate (60–62%), finely chopped or chips: 6 oz (170 g)
• Heavy cream: 1/2 cup (120 ml)
• Light corn syrup (optional, for shine): 1 tbsp

Toppings

• Mini Reese’s peanut butter cups: 8–10, halved, or 4 full-size cups chopped
• Roasted salted peanuts, roughly chopped: 1/3 cup (45 g)

Step-by-Step Instructions

Step 1: Prep the pans and oven

Preheat the oven to 350°F (177°C). Grease two 8-inch round cake pans, line the bottoms with parchment rounds, then lightly grease and flour the parchment and sides. This helps the delicate chocolate layers release cleanly.

Step 2: Mix the chocolate cake batter

In a large bowl, whisk together the flour, sugar, cocoa powder, baking powder, baking soda, and salt until no streaks remain. Add the eggs, buttermilk, oil, and vanilla. Whisk or mix on low just until smooth. Slowly stream in the very hot coffee while whisking; the batter will be thin and glossy. Scrape the bowl to ensure everything is incorporated.

Step 3: Bake the layers

Divide the batter evenly between the prepared pans (about 650–700 g per pan). Tap each pan lightly on the counter to release large bubbles. Bake on the center rack for 32 minutes, or until a toothpick inserted in the center comes out with a few moist crumbs and the centers spring back lightly to touch.

Step 4: Cool completely

Cool the cakes in the pans for 10 minutes, then run a thin knife around the edges, invert onto wire racks, and peel off the parchment. Let the layers cool completely, about 60 minutes. Level the tops with a long serrated knife if needed.

Step 5: Make the peanut butter buttercream

In a stand mixer fitted with the paddle (or using a hand mixer), beat the softened butter on medium speed until creamy and pale, 2–3 minutes. Add the peanut butter and beat until fluffy and combined, 1–2 minutes more. Reduce speed to low and gradually add the confectioners’ sugar and salt. Add the vanilla and 1/3 cup cream; beat on low to combine, then on medium for 1–2 minutes until smooth and spreadable. If needed, add 1–2 tbsp more cream to reach a silky, pipeable consistency.

Step 6: Make the ganache drip

Place the chopped chocolate in a heatproof bowl. Heat 1/2 cup heavy cream in a small saucepan over medium heat just until steaming and tiny bubbles appear at the edges (do not boil). Pour over the chocolate, cover the bowl with a plate, and let sit 2 minutes. Stir slowly from the center outward until glossy and smooth. Stir in the corn syrup if using. Let cool 10–15 minutes until slightly thickened and about 95–100°F—perfect for controlled drips.

Step 7: Assemble, frost, and decorate

Place one cake layer on a turntable or serving plate. Spread about 1 heaping cup of peanut butter buttercream evenly to the edges. Top with the second layer, cut side down. Apply a thin crumb coat of frosting over the cake and chill for 20 minutes to set. Add a final, thicker coat and smooth the sides and top. Using a spoon or squeeze bottle, apply ganache around the rim to create drips, then fill in the top, smoothing gently. Garnish with halved mini peanut butter cups and a scatter of chopped peanuts. Chill 15 minutes to set before slicing.

Pro Tips

• Weigh your batter into the pans for even layers and professional-looking results.
• Hot coffee intensifies chocolate flavor; if you prefer no coffee, use very hot water.
• For the cleanest slices, warm a sharp knife under hot water, wipe dry, and cut in one motion.
• Room-temperature ingredients blend more easily and help the cake rise evenly.
• For perfect drips, test one drip on the chilled cake; if it runs too far, let ganache cool a few more minutes.

Variations

• 9×13-inch sheet cake: Bake at 350°F (177°C) for 33 minutes. Frost the top with all the peanut butter buttercream, then add ganache swirls and toppings.
• Cupcakes: Yield about 24. Bake at 350°F (177°C) for 19 minutes. Pipe peanut butter frosting high and spoon ganache over each.
• Gluten-free: Use a 1:1 gluten-free baking flour blend by weight; keep all other steps and times the same.

Storage & Make-Ahead

Store the finished cake covered at cool room temperature for up to 1 day or refrigerate up to 4 days. Bring slices to room temperature for best texture. Unfrosted cake layers can be wrapped well and frozen for up to 2 months; thaw in the fridge overnight. Buttercream can be refrigerated up to 1 week or frozen up to 2 months; bring to room temperature and re-whip before using. Ganache keeps refrigerated up to 5 days; warm gently to loosen before dripping.

Nutrition (per serving)

Approximate for 1 of 12 slices: 900 calories; 55 g fat; 100 g carbohydrates; 12 g protein; 560 mg sodium; 72 g sugars; 6 g fiber. Values will vary based on specific ingredients and decorations used.