Peanut Butter Cup Dump Cake Recipe

There’s something about the combination of chocolate and peanut butter that makes a dessert feel both nostalgic and indulgent. If you’ve ever bitten into a Reese’s and wished you could have that same flavor in a cake form, then this Peanut Butter Cup Dump Cake is about to become your new go-to treat. It’s gooey, rich, and unapologetically decadent — perfect for potlucks, parties, or those evenings when your sweet tooth won’t take no for an answer.

This isn’t your ordinary dump cake. Instead of just tossing in a few ingredients, you’re layering in creamy peanut butter, marshmallow fluff, chocolate cake, and an avalanche of peanut butter cups. Every bite is a balance of fudgy chocolate, salty-sweet peanut butter, and gooey goodness that feels like it should be served at a bakery.

Ingredients

• 1 box chocolate cake mix
• 1 stick (½ cup) unsalted butter, melted
• 1 cup milk
• 1 cup peanut butter, creamy
• 1 jar (7 oz) marshmallow fluff
• 2 cups mini peanut butter cups, halved
• 1 cup chocolate chips
• ½ cup chopped peanuts (optional, for crunch)
• ½ cup caramel sauce (optional, for drizzling)

Instructions

1. Prepare the pan: Preheat your oven to 350°F (175°C). Grease a 9×13-inch baking dish.
2. Mix the base: In a mixing bowl, combine the chocolate cake mix, melted butter, and milk until just combined. Spread evenly in the prepared dish.
3. Layer peanut butter goodness: Warm the peanut butter slightly in the microwave (about 20 seconds) to make it pourable. Drizzle half over the cake batter.
4. Add marshmallow fluff: Dollop marshmallow fluff across the top and lightly swirl with a knife to create ribbons.
5. Top with candy: Scatter half of the peanut butter cups and half of the chocolate chips over the batter.
6. Bake it up: Bake for 35–40 minutes, until the center is set but still slightly gooey.
7. Finish with flair: Once out of the oven, drizzle remaining peanut butter and caramel sauce on top. Add the rest of the peanut butter cups, chocolate chips, and chopped peanuts.
8. Cool and serve: Let cool for at least 15 minutes before slicing. Serve warm with vanilla ice cream if desired.

Why You’ll Love This Cake

• Easy to make: Uses a boxed cake mix and pantry staples.
• Over-the-top flavor: Chocolate + peanut butter + marshmallow = dessert heaven.
• Crowd-pleasing: Perfect for birthdays, holidays, or casual weeknight indulgence.
• Flexible: Swap the chocolate cake for brownie mix or add caramel-filled chocolate chips for extra gooeyness.

Peanut Butter Cup Dump Cake

A rich and gooey chocolate cake layered with peanut butter, marshmallow fluff, and peanut butter cups for the ultimate decadent dessert.

Print Recipe Pin Recipe

Prep Time 15 minutes mins

Cook Time 40 minutes mins

Total Time 55 minutes mins

Servings: 12 squares

Course: Dessert

Cuisine: American

Calories: 420

Ingredients Equipment Method Notes

Ingredients

  

• 1 box chocolate cake mix
• 0.5 cup unsalted butter melted
• 1 cup milk
• 1 cup creamy peanut butter slightly warmed
• 7 oz marshmallow fluff
• 2 cups mini peanut butter cups halved
• 1 cup chocolate chips
• 0.5 cup chopped peanuts optional
• 0.5 cup caramel sauce optional, for drizzling

Equipment

• Mixing bowl
• 9×13 baking dish
• Spatula
• Microwave-safe bowl

Method

 

1. Preheat oven to 350°F (175°C) and grease a 9×13-inch baking dish.
2. Mix chocolate cake mix, melted butter, and milk until combined. Spread into dish.
3. Warm peanut butter slightly and drizzle half over batter.
4. Dollop marshmallow fluff on top and swirl lightly with a knife.
5. Top with half the peanut butter cups and half the chocolate chips.
6. Bake 35–40 minutes until mostly set in the center.
7. Drizzle remaining peanut butter and caramel over warm cake. Add remaining candy and peanuts.
8. Cool 15 minutes before serving.

Notes

Best served warm. Pair with vanilla ice cream for extra indulgence.

Storage Tips

• Store leftovers in an airtight container at room temperature for up to 2 days.
• Refrigerate for up to 5 days.
• Microwave individual slices for 20–30 seconds to bring back that gooey texture.