Reese’s Peanut Butter Earthquake Cake

So to confess: I am an addict when it comes to anything that resembles peanut butter and chocolate. The first time I baked this Reese’s Peanut Butter Earthquake Cake, I obviously could not keep my hands off it while it cooled. Those gooey chocolatey, peanut buttery, cream swirls are just calling your name, and every mouthful just feels right in any dessert mash-up.

Not a perfect cake you would find at a patisserie; rather, it is this messy little thing where all the good stuff crashes together. Just picture this: a chocolate cake base with tangy cream cheese pockets, the drizzling mixture of peanut butter, and chunks of Reese’s cups all baked together until crackled and bubbling, hence the term ‘earthquake.’ It is rustic, decadent, and so much fun to prepare.

And the best part? You don’t need advanced baking skills or fancy equipment. Just some pantry basics, a few Reese’s cups, and a little patience while it bakes (the hardest part, honestly).

Why This Recipe Is Special

What makes this cake beautiful is its personality. It doesn’t bother itself much; it might never be a candidate for a beauty pageant, and that’s why it works. The swirly tops are not uniform, the cracks on the top are not symmetrical, and molten, slightly crunchy pockets are composed mainly of just chocolate and peanut butter, including all of that in the best homemade way. And best of all, it tastes like three desserts in one: chocolate cake, cheesecake, and peanut butter candy bar.

Why You’ll Love This Recipe

Here’s why I think you’ll fall in love with this cake too:

• Flavor overload – Chocolate, peanut butter, cream cheese, and Reese’s cups all in one bite.
• Foolproof – Even if it cracks or bubbles, it still looks gorgeous and tastes incredible.
• Crowd-pleaser – Bring this to a gathering, and watch people fight over the last slice.
• Flexible – Swap in brownies, try different candies, or even drizzle caramel on top.
• Comfort food – This is the kind of cake that feels like a hug after a long day.

Tools You’ll Need

I promise—you don’t need a fancy kitchen setup. Here’s what you’ll want:

• 9×13-inch baking dish (23×33 cm) – The perfect size for this gooey cake.
• Mixing bowls (medium and large) – One for cake batter, one for cream cheese mix.
• Hand or stand mixer – To whip the cream cheese filling until smooth.
• Rubber spatula – For scraping every last bit of peanut butter goodness.
• Measuring cups and spoons (or scale) – Accuracy matters with baking, so I like using grams.
• Knife and cutting board – For chopping up the Reese’s cups into chunks.

Ingredients (US + Metric)

For the Cake Base:

• 1 box chocolate cake mix (15.25 oz / 432 g) + ingredients listed on box (usually eggs, oil, water)
• 1/2 cup (120 ml) milk

For the Cream Cheese Filling:

• 8 oz (226 g) cream cheese, softened
• 1/2 cup (115 g) unsalted butter, softened
• 3 1/2 cups (420 g) powdered sugar

For the Peanut Butter Layer:

• 1/2 cup (128 g) creamy peanut butter

Add-Ins and Toppings:

• 1 1/2 cups (180 g) Reese’s Peanut Butter Cups, chopped
• 1/2 cup (90 g) chocolate chips (optional but worth it)

Step-by-Step Instructions

1. Preheat and prep
2. Heat your oven to 350°F (175°C). Grease your 9×13 pan with butter or spray so nothing sticks.
3. Mix the cake base
4. In a large bowl, prepare the cake mix according to the box instructions, but add 1/2 cup milk for extra richness. Pour this into your greased pan and smooth it out.
5. My tip: Don’t worry if it looks thin—this is the foundation for all the gooey magic.
6. Make the cream cheese filling
7. In another bowl, beat the cream cheese and butter together until smooth and fluffy. Slowly add powdered sugar, mixing until creamy.
8. This layer is what gives you those pockets of sweet tanginess that balance all the chocolate.
9. Spoon and swirl
10. Drop spoonfuls of the cream cheese mixture randomly over the cake batter. Do the same with dollops of peanut butter. Use a butter knife to gently swirl everything together—but don’t overdo it. You want marbled ribbons, not a blended mess.
11. Add the candy
12. Sprinkle chopped Reese’s cups and chocolate chips across the top. Press them lightly so they sink in just a bit.
13. Bake it up
14. Slide it into the oven and bake for 40–45 minutes. The top should look cracked and bubbly—like an “earthquake.” A toothpick may come out slightly gooey, and that’s okay.
15. Cool (the hardest part)
16. Let the cake cool in the pan for at least 20 minutes before slicing. It sets up as it rests, but it’s also ridiculously good warm with a scoop of ice cream.

Serving Ideas

• Top with vanilla ice cream for a sundae cake, where the real fun begins.
• A drizzle of warm chocolate or caramel sauce will send this dessert into further decadence.
• Serve slightly chilled for a firmer texture (this is great for pretty slices).

Variations & Customizations

• Use a brownie mix instead of one for cake for an even fudgier base.
• If you like Snickers, Milky Way, or KitKats better than Reese’s, feel free to switch.
• Try crunchy peanut butter for added texture.
• Sprinkle a little sea salt on top to balance the sweetness.

Storage & Make-Ahead

• Room temperature: Great covered for 2 days.
• Fridge: Airtight container up to 5 days.
• Freezer: Wrap each slice individually and freeze for up to 2 months. Thaw overnight for serving.

Pro Tips & Mistakes to Avoid

Here’s me spilling my best secrets:

• Don’t over-swirl. A couple of turns with your knife is enough.
• Make sure cream cheese and butter are softened—cold lumps won’t mix well.
• Don’t panic if it looks messy going into the oven. It’s supposed to!
• Let it cool before cutting, unless you don’t mind messy (but delicious) squares.
• Taste test while warm—you deserve it.

Recipe Details

• Yield: About 12–15 servings
• Prep Time: 15 minutes
• Cook Time: 40–45 minutes
• Total Time: 1 hour

Nutrition (per serving, based on 15 servings):

• Calories: ~420
• Fat: 24 g
• Carbs: 47 g
• Protein: 6 g

Final Thoughts

If you’ve made it this far, you’re probably already imagining that first bite of melty chocolate, creamy peanut butter, and chunks of Reese’s. Trust me—it’s as good as it sounds, maybe better. This isn’t a cake that sits around untouched; it disappears fast.