There’s something about chocolate and peanut butter that feels like it fixes everything, you know? Like even on the roughest day — when nothing goes right, the sink’s full of dishes, and you’re just staring at your phone wondering what to make — this combo never lets you down.
The first time I made this cake, it wasn’t for a birthday or anything fancy. It was one of those “I just need something good” days. I’d had a box of chocolate cake mix sitting in the pantry forever, a tub of peanut butter that was begging to be used, and this half-formed idea that maybe I could turn it into something warm and over-the-top. So I just… went for it. No plan, no pressure.
And wow. When it came out of the oven — puffed and crackly and smelling like pure comfort — I actually laughed. It’s the kind of cake that feels homemade even though it starts from a box. The peanut butter layer sort of melts into the chocolate batter while it bakes, so it ends up all swirly and gooey and perfectly imperfect. You get bites that are rich and fudgy, then others that are creamy and sweet, with little pockets of melted chocolate and melty Reese’s cups all over the top. It’s honestly kind of ridiculous in the best wa
It’s the kind of dessert that doesn’t need frosting, or rules, or even a plate — you just grab a spoon and go for it while it’s still warm. The top cracks a little, like an earthquake cake, and when you dig in, it’s this soft, molten mix of chocolate and peanut butter that tastes like nostalgia. Like childhood sleepovers, movie nights, and those moments where you just want dessert to feel easy.
Ingredients
1 (15.25 oz) box chocolate cake mix (plus eggs, oil, and water as directed on box)
½ cup (1 stick) unsalted butter, softened
8 oz cream cheese, softened
½ cup creamy peanut butter (not natural or oily kinds)
½ teaspoon vanilla extract
4 cups powdered sugar, sifted
½ cup semi-sweet chocolate chips
1 cup mini Reese’s Peanut Butter Cups, halved
Directions
- Preheat the oven:
350°F (175°C). Grease a 9×13-inch baking dish with butter or spray. You’ll want this cake to slide out easily later. - Mix the chocolate cake:
Prepare the cake mix as it says on the box — nothing fancy. Pour it into your pan, smooth it out, and don’t bake it yet. - Make the peanut butter layer:
Beat the butter and cream cheese together until smooth — no lumps. Add peanut butter and vanilla, beat again until silky. Then, slowly mix in the powdered sugar a bit at a time (unless you want your kitchen covered in a powdered sugar cloud — no judgment). - Layer it up:
Drop spoonfuls of the peanut butter mixture all over the unbaked chocolate batter. Use a spoon or spatula to spread it around a little. Don’t worry about it looking pretty — the messier, the better. - Add the good stuff:
Sprinkle chocolate chips all over, then scatter your chopped mini Reese’s on top. - Bake:
Pop it in the oven for 45–55 minutes. The edges will look firm, the middle will jiggle slightly — that’s perfect. It’s meant to be soft inside. - Cool (a little):
Let it rest for 20–30 minutes. You can slice it, but honestly, it’s best served with a spoon while it’s still warm and gooey.
Recipe FAQs
1: Can I use a homemade chocolate cake instead of box mix?
Sure, if you want to. But honestly? The box mix works perfectly here. It’s soft, consistent, and plays well with the rich peanut butter layer. If you go homemade, make sure it’s a moist recipe — dry cake ruins the fun.
2: My peanut butter layer sank into the cake — is that okay?
Totally. That’s what gives it the “earthquake” look! The peanut butter sinks, melts, and creates those delicious pockets of flavor. It’s supposed to look rustic, messy, and kind of wild.
3: Can I use chunky peanut butter?
You can, but it’ll change the texture. Smooth peanut butter gives that creamy, frosting-like swirl. Chunky will add a little crunch, which isn’t bad — just different.
4: What’s the best way to serve it?
Warm, with a spoon. Maybe a scoop of vanilla ice cream if you’re feeling extra. It’s not the kind of cake that needs to be perfect slices — it’s a cozy, dig-in kind of dessert.
5: Can I make this ahead for a party?
You can bake it the day before, but keep it covered at room temp. Reheat it in the oven or microwave just before serving to bring back the gooeyness. Trust me — that warm, slightly melty texture is everything.
Reese’s Peanut Butter Cake
4
servings30
minutes40
minutes300
kcalIngredients
1 box chocolate cake mix (plus eggs, oil, and water as directed on box)
½ cup (1 stick) unsalted butter, softened
8 oz cream cheese, softened
½ cup creamy peanut butter (not natural or oily kinds)
½ teaspoon vanilla extract
4 cups powdered sugar, sifted
½ cup semi-sweet chocolate chips
1 cup mini Reese’s Peanut Butter Cups, halved
Directions
- Preheat the oven:
- 350°F (175°C). Grease a 9×13-inch baking dish with butter or spray. You’ll want this cake to slide out easily later.
- Mix the chocolate cake:
- Prepare the cake mix as it says on the box — nothing fancy. Pour it into your pan, smooth it out, and don’t bake it yet.
- Make the peanut butter layer:
- Beat the butter and cream cheese together until smooth — no lumps. Add peanut butter and vanilla, beat again until silky. Then, slowly mix in the powdered sugar a bit at a time (unless you want your kitchen covered in a powdered sugar cloud — no judgment).
- Layer it up:
- Drop spoonfuls of the peanut butter mixture all over the unbaked chocolate batter. Use a spoon or spatula to spread it around a little. Don’t worry about it looking pretty — the messier, the better.
- Add the good stuff:
- Sprinkle chocolate chips all over, then scatter your chopped mini Reese’s on top.
- Bake:
- Pop it in the oven for 45–55 minutes. The edges will look firm, the middle will jiggle slightly — that’s perfect. It’s meant to be soft inside.
- Cool (a little):
- Let it rest for 20–30 minutes. You can slice it, but honestly, it’s best served with a spoon while it’s still warm and gooey.
