Ingredients

1¾ cups all-purpose flour

¾ cup unsweetened cocoa powder

1 cup granulated sugar

½ cup light or dark brown sugar

2 eggs, room temperature

½ cup vegetable oil or melted butter

1 cup buttermilk or milk with 1 tbsp vinegar

1 cup hot coffee, slightly cooled

2 tsp vanilla extract

1½ tsp baking soda

1½ tsp baking powder

½ tsp salt

1 tbsp mayonnaise (optional for extra moisture)

1 cup creamy or crunchy peanut butter

½ cup softened butter

2½ cups powdered sugar

2–4 tbsp heavy cream, adjust for consistency

1 tsp vanilla extract

1 pinch salt (optional)

½ cup mini chocolate chips (for garnish or mix-in)

½ cup chopped peanuts (for texture)

¼ cup chocolate ganache (for drizzling)

½ cup crushed peanut butter cups (for topping)

Instructions

Step 1: Preheat the oven to 350°F (175°C). Grease two 9-inch round cake pans and line the bottoms with parchment paper to prevent sticking.

Step 2: In a large bowl, whisk together the all-purpose flour, cocoa powder, granulated sugar, brown sugar, baking soda, baking powder, and salt.

Step 3: In a separate bowl, beat the eggs, then add the vegetable oil (or melted butter), buttermilk, vanilla extract, and mayonnaise if using. Mix well.

Step 4: Combine the wet ingredients with the dry ingredients and stir until just blended. Slowly add the hot coffee and mix until smooth.

Step 5: Divide the batter evenly between the prepared pans and bake for 28 to 32 minutes, or until a toothpick inserted into the center comes out clean.

Step 6: Allow the cakes to cool in the pans for 10 minutes, then turn them out onto wire racks to cool completely before frosting.

Step 7: To make the frosting, beat the softened butter until fluffy. Add the peanut butter and continue to beat until combined.

Step 8: Gradually add the powdered sugar, mixing well after each addition. Add heavy cream a tablespoon at a time until the frosting reaches a spreadable consistency. Mix in vanilla extract and a pinch of salt if desired.

Step 9: Place one cake layer on a serving plate and spread a layer of frosting over the top. Add the second cake layer and frost the top and sides evenly.

Step 10: Garnish the cake with mini chocolate chips, chopped peanuts, drizzle with chocolate ganache, and sprinkle crushed peanut butter cups on top for added texture and flavor.

Tips & Variations

Use freshly brewed coffee to enhance the chocolate flavor without adding a strong coffee taste.

Swap mayonnaise for sour cream if preferred; both add moisture to the cake.

For a crunchy frosting, mix in chopped peanuts or use crunchy peanut butter instead of creamy.

If you want a lighter frosting, reduce the amount of powdered sugar and increase heavy cream slightly.

Try adding a pinch of cinnamon or espresso powder to highlight the chocolate and peanut butter.

Storage

Store the cake covered in an airtight container or cake dome at room temperature for up to 2 days. For longer storage, refrigerate for up to 5 days. Bring the cake to room temperature before serving for the best flavor and texture. Leftover frosting can also be refrigerated and gently reheated before use.

FAQs

Can I make this cake gluten-free?

Yes, substitute the all-purpose flour with a gluten-free baking blend, ensuring it contains xanthan gum for structure. Baking times may vary slightly, so check doneness with a toothpick.

Can I freeze the cake?

Absolutely. Wrap frosted or unfrosted cake layers tightly in plastic wrap and then foil. Freeze for up to 3 months. Thaw overnight in the refrigerator and bring to room temperature before serving.