A peanut butter cup goes into each cupcake before it bakes. That's the whole trick, and it's why these get called box cupcakes. You use a box of chocolate cake mix, and the candy does the rest.
You need 18 peanut butter cups for 12 cupcakes. Twelve go in the middle, and the other six get cut in half and pressed into the frosting on top. One cup of vanilla frosting plus three quarters of a cup of peanut butter makes the topping.
The bake is 375 F for 20 minutes. Don't skip the cooling step. Frosting goes on warm cupcakes and turns into a puddle.
Step-by-Step Instructions
1. Heat the oven
Set the oven to 375 F and line a 12-cup muffin tin with paper liners. Give yourself a full rack in the middle.
2. Mix the batter
Prepare the chocolate cake mix in a large bowl following the package directions. Stop mixing when the dry streaks disappear. Overmixing makes the cupcakes tough.
3. Fill halfway
Spoon batter into the liners until each one is about half full. Keep the amounts even so they bake at the same rate.
4. Add the cups
Set one whole peanut butter cup into each liner and press it down lightly. Spoon the rest of the batter over the top until each liner is about three quarters full.
5. Bake 20 minutes
Bake for 20 minutes. A toothpick inserted off to the side of the candy should come out with a few moist crumbs, not wet batter.
6. Cool
Leave the cupcakes in the tin for 5 minutes, then move them to a rack. Wait until they're completely cool before frosting.
7. Make the frosting
Stir the peanut butter and vanilla frosting together in a bowl until smooth. Taste it. If you want more peanut butter flavor, add another spoonful.
8. Cut the remaining cups
Halve the six leftover peanut butter cups. A warm knife cuts cleaner, so run it under hot water and dry it between cuts.
9. Frost and top
Pipe the frosting onto each cooled cupcake with a star tip, or spread it with a knife. Press a peanut butter cup half into the top of each one.
Pro Tips
How to Store Chocolate Peanut Butter 'Box' Cupcakes
Refrigerator
Keep frosted cupcakes in a sealed container in the fridge for up to 4 days. Let them sit out 20 minutes before eating so the cake softens back up.
Freezer
Freeze unfrosted cupcakes wrapped tightly for up to 2 months. Thaw at room temperature, then frost. Frosted cupcakes freeze too but the swirl can smudge.
Reheating
You don't need to reheat these. If they've been in the fridge, 15 to 20 seconds in the microwave brings the center back to soft.
Frequently Asked Questions
Q: Can I use mini peanut butter cups instead?
You can, but you'll need more of them and the center pocket will be smaller. Use two minis stacked in the middle of each cupcake and a third on top of the frosting.
Q: Why did my peanut butter cup sink to the bottom?
Usually too much batter underneath it or a hard push. Fill the liner halfway, set the cup on the batter, then cover it. The batter rises around the candy as it bakes.
Q: How do I know the cupcakes are done without cutting into the candy?
Insert the toothpick about an inch from the edge, not in the center where the cup sits. You're looking for a few moist crumbs. The cake pulls slightly away from the liner when it's ready.
Q: Can I make these ahead of time?
Bake and cool the cupcakes a day ahead and store them covered at room temperature. Frost them the day you serve, because the peanut butter frosting dries out after about 24 hours.
Q: Does the peanut butter frosting need refrigeration?
Yes, once it's on the cupcakes. The frosting is dairy-based, so keep them cold if they'll sit out longer than a couple of hours.
Chocolate Peanut Butter Box Cupcakes With a Hidden Cup
Chocolate cupcakes with a whole peanut butter cup baked inside, topped with peanut butter frosting and a cup half. One box of cake mix, 12 cupcakes.
Ingredients
Instructions
- 1Heat the oven — Set the oven to 375 F and line a 12-cup muffin tin with paper liners. Give yourself a full rack in the middle.
- 2Mix the batter — Prepare the chocolate cake mix in a large bowl following the package directions. Stop mixing when the dry streaks disappear. Overmixing makes the cupcakes tough.
- 3Fill halfway — Spoon batter into the liners until each one is about half full. Keep the amounts even so they bake at the same rate.
- 4Add the cups — Set one whole peanut butter cup into each liner and press it down lightly. Spoon the rest of the batter over the top until each liner is about three quarters full.
- 5Bake 20 minutes — Bake for 20 minutes. A toothpick inserted off to the side of the candy should come out with a few moist crumbs, not wet batter.
- 6Cool — Leave the cupcakes in the tin for 5 minutes, then move them to a rack. Wait until they're completely cool before frosting.
- 7Make the frosting — Stir the peanut butter and vanilla frosting together in a bowl until smooth. Taste it. If you want more peanut butter flavor, add another spoonful.
- 8Cut the remaining cups — Halve the six leftover peanut butter cups. A warm knife cuts cleaner, so run it under hot water and dry it between cuts.
- 9Frost and top — Pipe the frosting onto each cooled cupcake with a star tip, or spread it with a knife. Press a peanut butter cup half into the top of each one.
Darnell covers air fryer recipes and slow cook meals, with a steady side of eggs and breakfast casseroles for people cooking on a tight schedule. He writes in a blunt, test-it-again voice and flags the mistakes that ruin texture, from soggy fries to rubbery eggs. Every post gives timings, temperatures, and a fallback if your machine runs hot.
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