Ultimate Peanut Butter Cup Cake Recipe
A fudgy chocolate cake infused with creamy peanut butter frosting and studded with mini peanut butter cups, this dessert is a showstopper for celebrations or anytime indulgence.
Why You’ll Love This Cake:
- Layers of rich chocolate and creamy peanut butter in every bite
- Swirled frosting gives a visually stunning, marbled effect
- Perfect for parties—simple to make and endlessly customizable
- A dream for peanut butter lovers looking for maximum flavor
Ingredients & Easy Swaps
| Ingredient | Quantity | Suggested Swap |
|---|---|---|
| Boxed chocolate cake mix | 1 (9×13-inch recipe) | Gluten-free cake mix |
| Eggs | 4 large | Vegan egg replacer or flax eggs |
| Milk | 1 cup (240 ml) | Almond or oat milk |
| Vanilla extract | 1 tsp | Optional — enhances sweetness |
| Peanut butter | 1 cup (240 g) | Almond or cashew butter |
| Butter (softened) | 1 stick (½ cup / 115 g) | Plant-based margarine or coconut oil |
| Chocolate syrup | Several generous squirt | Melted chocolate or chocolate ganache |
| Mini peanut butter cups | ~30, chopped | Chopped chocolate chips or peanut butter chips |
| Powdered sugar | ~2 cups (250 g) | Coconut sugar powder (higher calorie caveat) |
| Additional milk for frosting | As needed | |
| Extra toppings: chocolate syrup & peanut butter cups | To finish | Crushed nuts, sprinkles, or caramel drizzle |
Side Notes & Variations
- Make it gluten-free by using a GF cake mix and confirming peanut butter is GF.
- Add chocolate chips or Reese’s Pieces directly into batter for extra texture.
- Serving Suggestion: Pair with a scoop of ice cream or a glass of cold milk.
Ultimate Peanut Butter Cup Cake
Course: DessertCuisine: American, Comfort BakingDifficulty: Easy, IntermediateA fudgy chocolate cake infused with creamy peanut butter frosting and studded with mini peanut butter cups—this dessert is a showstopper for celebrations or anytime indulgence.
Ingredients
1 (9×13-inch recipe) Boxed chocolate cake mix
4 large Eggs
1 cup (240 ml) Milk
1 tsp Vanilla extract
1 cup (240 g) Peanut butter
1 stick (½ cup / 115 g) Butter
Several generous squirt Chocolate syrup
30 chopped Mini peanut butter cups
2 cups (250 g) Powdered sugar
Additional milk for frosting
Extra toppings: chocolate syrup & peanut butter cups
Directions
- Preheat & Make Batter
Preheat your oven to 350 °F (175 °C).
In a large bowl, mix the cake mix, eggs, 1 cup milk, vanilla, 1 cup peanut butter, and ½ cup softened butter.
Pour the batter into a greased 9×13-inch baking dish.
- Swirl Frosting Base
In another bowl, cream ½ cup butter, 1 cup peanut butter, and a splash of milk until combined. Gradually stir in powdered sugar until it forms a thick frosting.
Drop half the frosting mixture in dollops over the cake batter and add generous squiggles of chocolate syrup.
Use a butter knife to swirl the frosting and syrup through the batter. Be sure your swirls reach edges for even marbling.
Press half of the chopped peanut butter cups gently into the batter. - Bake
Bake for 35–40 minutes, until it’s set but slightly soft in the center. Remove and let rest for 15–20 minutes. - Frost & Finish
Spread the remaining frosting on top. Drizzle more chocolate syrup and scatter remaining peanut butter cups over the surface.
Notes
- Store in the fridge due to the frosting, and bring to room temperature before serving for the best flavor and texture
