If you’re a dessert lover who swoons over the combo of chocolate and peanut butter, then this Chocolate Peanut Butter Earthquake Cake is about to become your favorite guilty pleasure. Imagine dark chocolate fudge cake rippled with creamy peanut butter, swirls of sweetened cream cheese, and a scattering of chocolate chips and peanut butter cups that melt right into every bite. It’s gooey, rich, indulgent—and downright irresistible.
This cake is called “earthquake” for a reason—it doesn’t hold back. The layers swirl and crack during baking, creating a marbled effect that makes each piece uniquely stunning and totally crave-worthy.
Ingredients
For the Cake Base
- 1 box dark chocolate fudge cake mix (plus ingredients listed on the box: oil, eggs, and water)
For the Creamy Peanut Butter Swirl
- 8 oz (1 block) cream cheese, softened
- ½ cup butter, softened
- ½ cup creamy peanut butter
- 1 teaspoon vanilla extract
- 4 cups powdered sugar (confectioner’s sugar)
For the Toppings
- ½ cup chocolate chips (semi-sweet or milk chocolate)
- 1 cup miniature Reese’s peanut butter cups, unwrapped and halved
Preparation
Mixing the Chocolate Cake Base
Preheat your oven to 350°F (175°C). Prepare a 9×13-inch baking dish by greasing it with butter or spraying with nonstick cooking spray. Set aside.
In a large mixing bowl, prepare the dark chocolate fudge cake mix according to the package instructions—typically this will require oil, eggs, and water. Mix until well combined and smooth. Pour the cake batter into the prepared baking dish, spreading it out evenly with a spatula.
Set the pan aside while you prepare the rich peanut butter cream layer.
Making the Peanut Butter Cream Cheese Swirl
In another large bowl, combine softened cream cheese, softened butter, peanut butter, and vanilla extract. Using a hand mixer or stand mixer, beat until the mixture is smooth and creamy.
Gradually add powdered sugar, one cup at a time, beating well after each addition. This will form a thick, sweet peanut butter cream that’s soft enough to spread but sturdy enough to hold its shape during baking.
Using a spoon or cookie scoop, drop spoonfuls of the peanut butter mixture across the surface of the chocolate cake batter in the baking dish. Do not fully mix or stir it in—just lightly spread or swirl the dollops so they sit partially submerged in the chocolate layer. This creates the signature “earthquake” appearance once baked.
Adding the Final Touches
Now sprinkle the halved mini Reese’s peanut butter cups evenly over the top of the cake. Follow with a generous handful of chocolate chips. As the cake bakes, these melt slightly into the batter, giving every bite a burst of melted chocolate and peanut butter goodness.
Baking the Cake
Place the baking dish into the preheated oven and bake for 45–50 minutes. Begin checking at the 45-minute mark by inserting a toothpick into the center. It should come out with a few moist crumbs but not wet batter.
Remember, this is a gooey-style dessert, so don’t overbake—some soft spots are expected and part of the charm. The top should appear cracked and marbled with golden brown peanut butter swirls and melted candies.
Allow the cake to cool for 10–15 minutes before serving for best results. This cake is fantastic warm, especially when paired with a scoop of vanilla ice cream.
Serving Suggestions
- Best enjoyed warm: Serve slices fresh from the oven for the ultimate gooey experience.
- With ice cream: Vanilla ice cream is a perfect creamy contrast to the rich, warm chocolate.
- Drizzle with extra chocolate syrup or caramel if you’re feeling indulgent.
- Whipped cream and chopped peanuts can also add a fun, light contrast in texture and flavor.
Tips for the Best Earthquake Cake
- Use full-fat cream cheese for the creamiest, richest texture.
- Don’t overmix the peanut butter swirl into the cake. You want to see pockets and streaks, not a fully blended batter.
- Let the cake rest for at least 10 minutes before slicing. It will firm up slightly as it cools.
- Freeze the mini Reese’s for 10 minutes before chopping to avoid melting as you handle them.
- Try different cake mixes like milk chocolate, devils food, or even a brownie mix for variation.
- Line your pan with parchment paper if you want easy removal and clean slicing.
Variations to Try
- Nutty twist: Add chopped roasted peanuts or pecans to the batter for a crunchy element.
- Salted caramel version: Swirl in a few spoonfuls of caramel sauce with the peanut butter mixture.
- Brownie base: Use a brownie mix instead of chocolate cake mix for an extra fudgy version.
- Spicy kick: Add a pinch of cayenne pepper or chili powder to the chocolate batter for a subtle, spicy note.
- White chocolate chips: Swap in or add white chocolate for a sweet contrast.
Storage and Freezing
This cake stores well and stays moist for days.
Refrigerator:
Store in an airtight container in the fridge for up to 5 days. Reheat individual slices in the microwave for 20–30 seconds to bring back that fresh-from-the-oven gooeyness.
Freezer:
Wrap individual slices in plastic wrap and freeze in a zip-top bag for up to 2 months. Thaw overnight in the fridge and warm in the oven or microwave before serving.
Frequently Asked Questions
Why is it called “earthquake cake”?
The cake gets its name from its cracked, marbled appearance after baking. As the cream cheese and peanut butter layer sinks and swirls through the chocolate cake during baking, the top cracks and shifts—much like an earthquake might do.
Can I make this ahead of time?
Yes! It’s perfect to bake a day ahead. Just reheat slices in the microwave before serving for best texture and flavor.
What type of cake mix works best?
A dark chocolate fudge cake mix is ideal for richness, but any chocolate cake mix will do. You can even use a homemade chocolate cake batter if preferred.
Can I make this without peanut butter?
You can substitute almond butter or cookie butter if you’re avoiding peanut butter, though the flavor will change slightly. For a nut-free version, use sunflower seed butter.
Is this cake gluten-free?
Not as written, but it can be made gluten-free using a certified GF cake mix and checking that your mix-ins are gluten-free as well.
Final Thoughts
This Chocolate Peanut Butter Earthquake Cake is everything a dessert should be: gooey, rich, sweet, and absolutely over-the-top in the best way possible. With its marbled layers of chocolate cake and peanut butter cream, crunchy Reese’s pieces, and melty chocolate chips, every bite is pure bliss.
It’s a crowd-pleaser, easy to make, and perfect for holidays, potlucks, or those days when only something outrageously delicious will do.