5-Ingredient Peanut Butter Cup Dump Cake
This 5-ingredient peanut butter cup dump cake is a gooey, chocolate-peanut butter dessert that comes together with almost no work.
You literally dump cake mix, butter, sweetened condensed milk, peanut butter, and peanut butter cups into a pan and bake. The result is a fudgy, candy-studded treat that tastes like a giant Reese’s cup in cake form.
Why This Cake Stays in the Rotation
I keep this recipe in my back pocket for last-minute potlucks or when a chocolate craving hits hard. It’s all the rich, salty-sweet flavor of a peanut butter cup with the warm, spoonable texture of a cobbler.
No mixer, no bowls to wash, and a whole pan feeds a crowd. The condensed milk soaks into the cake mix and bakes into a soft, pudding-like layer, while the butter crisps the top and the peanut butter cups melt into pockets of molten chocolate and peanut butter.
It’s messy, irresistible, and exactly what a weeknight dessert should be.
Ingredients
- 1 box (15.25 oz) chocolate cake mix: any standard brand works.
- 3/4 cup unsalted butter, melted: salted butter is fine, just skip any added salt.
- 1 can (14 oz) sweetened condensed milk: full-fat, not evaporated milk.
- 1 cup creamy peanut butter: not the natural kind that separates.
- 20 mini peanut butter cups: (or 10 regular, roughly chopped): plus a few extra for topping if you like.
Variations / Substitutions
- Use yellow or vanilla cake mix: gives a more peanut-butter-forward flavor.
- Try crunchy peanut butter: adds little bits of texture throughout.
- Swap in white chocolate peanut butter cups: a sweeter, creamier twist.
- Use coconut condensed milk: makes the cake dairy-free alongside the butter swap.
- Scatter in a handful of chocolate chips: extra pockets of melty chocolate never hurt.
For an even quicker peanut butter fix, try my 3-Ingredient Peanut Butter Cookies.
How to Make Peanut Butter Cup Dump Cake
Step 1: Scatter the Cake Mix
Preheat the oven to 350°F (180°C) and grease a 9×13-inch baking pan. Pour the entire box of chocolate cake mix into the pan and spread it into an even layer with your fingers or a spatula.
The dry mix will look powdery and even. Do not worry about it being tidy; it all comes together in the oven.
Step 2: Pour and Dollop the Wet Ingredients
Drizzle the 3/4 cup melted butter evenly over the cake mix, covering as much of the surface as you can. Slowly pour the 14-ounce can of sweetened condensed milk over the top, letting it pool in a few spots. Dollop the 1 cup creamy peanut butter by spoonfuls across the pan, then scatter the 20 mini peanut butter cups (chopped if large) evenly over everything.
The pan will look a glorious mess, and that is exactly right.
Step 3: Bake the Cake
Slide the pan into the preheated oven and bake for 30 to 35 minutes. You will know it is ready when the edges are deeply golden and bubbling, and the center is set but still jiggles a little.
A toothpick will not come out clean because the whole thing is gooey. Look for melted peanut butter cups and a shiny, crackly top. The smell of warm chocolate and peanut butter will tell you it is close.
Step 4: Slice and Serve Warm
Let the cake cool in the pan for at least 10 minutes. This gives it time to set up enough to slice. Use a spatula to cut generous squares right from the pan and serve while still warm.
Each scoop has ribbons of fudge, melted peanut butter, and soft cake. A big spoon and a scoop of vanilla ice cream are all you need.
A Few Notes Before You Start
- Go for full-fat sweetened condensed milk. Low-fat or sugar-free versions will not set up the same and can turn watery.
- If the top browns before the center is set, loosely tent the pan with foil for the last 5 to 10 minutes.
- Chop the peanut butter cups roughly. A few left whole will melt into small pools, while larger pieces stay chunky.
- For the cleanest slices, let the cake cool completely, then reheat individual portions. But we usually just spoon it straight from the pan.
Bake times by pan size:
| Pan Size | Batter Amount | Bake Time |
|---|---|---|
| 9×13 inch | Full recipe | 30 to 35 mins |
| 8×8 inch | Half recipe | 25 to 30 mins |
Storing Leftovers
- Refrigerate: Cover the pan tightly or transfer to an airtight container. It keeps well for up to 4 days.
- Reheating: Microwave individual portions for 20 to 30 seconds until warm and gooey again.
What To Serve With Peanut Butter Cup Dump Cake
A scoop of vanilla ice cream against the warm cake is the classic move. A drizzle of hot fudge pushes it further, and a pinch of flaky sea salt on top cuts through the sweetness in the best way.
Frequently Asked Questions
Can I use a gluten-free cake mix?
Yes. A gluten-free chocolate cake mix works well with no other changes needed.
What if I only have regular-sized peanut butter cups?
Chop about 10 regular cups into quarters and use them instead. They will melt into similar gooey pockets.
Can I leave out the peanut butter?
You can, but the cake will not be as rich. Add an extra handful of peanut butter cups and double the sweetened condensed milk to make up for the moisture loss.
Can I prep this ahead of time?
Assemble the unbaked cake, cover it, and refrigerate for up to 4 hours. Bring it to room temp while the oven preheats, then bake as directed, adding about 5 minutes.
Peanut Butter Cup Dump Cake Recipe
Ingredients
Method
- Preheat oven to 350°F (180°C). Grease a 9×13-inch pan. Scatter the dry cake mix evenly in the pan.
- Drizzle the melted butter evenly over the cake mix, then pour the sweetened condensed milk over the top. Dollop the peanut butter by spoonfuls and scatter the chopped peanut butter cups.
- Bake for 30 to 35 minutes, until edges are bubbly and the center is set but jiggles slightly.
- Cool in the pan for 10 minutes, then slice and serve warm.
