Introduction

These Chocolate Peanut Butter Filled Cupcakes combine rich chocolate cake with a creamy peanut butter marshmallow filling and fluffy peanut butter buttercream. Perfect for peanut butter lovers, they offer a delicious surprise inside and an irresistible frosting on top.

The image shows two dark chocolate cupcakes cut in half, revealing a gooey caramel center inside the rich, moist chocolate cake layer. On top of each cupcake is a thick layer of light brown, fluffy frosting with a creamy texture. Each cupcake is topped with a half of a smooth, shiny, dark chocolate peanut butter cup. The cupcakes rest on white cupcake liners, placed on a white marbled surface. In the background, there is a whole chocolate peanut butter cup near the cupcakes. photo taken with an iphone --ar 4:5 --v 7

Ingredients

1 cup All-purpose flour
1/2 cup Unsweetened cocoa powder
1/4 tsp Baking soda
1 tsp Baking powder
3/4 cup White granulated sugar
1/4 cup Brown sugar (packed, light or dark)
1/4 tsp Salt
1/3 cup Oil (canola or vegetable)
2 Large eggs (room temperature)
2 tsp Pure vanilla extract
1/2 cup Buttermilk (room temperature)
1/2 cup Hot water (steaming)
1/3 cup Peanut butter (smooth)
1/3 cup Marshmallow fluff
2 tbsp Milk
1/2 tsp Ground cinnamon
1 1/2 tbsp Powdered sugar
1 cup Unsalted butter (slightly cold)
1 cup Peanut butter (creamy)
3 cups Sifted powdered sugar
2 tsp Pure vanilla extract
1/4 cup Heavy whipping cream (cold)
Reese’s peanut butter cups (for decoration)

Instructions

Step 1: Preheat the oven to 350°F (175°C) and line a 12-cup muffin pan with paper liners.
Step 2: In a small bowl, sift together the flour, cocoa powder, baking soda, baking powder, white sugar, brown sugar, and salt. Set aside.
Step 3: In a separate bowl, whisk the oil, vanilla extract, eggs, and buttermilk until combined. Slowly pour this wet mixture into the dry ingredients and whisk gently until just combined.
Step 4: Heat the water until steaming. Add it very slowly into the batter, whisking gently as you pour to prevent cooking the eggs.
Step 5: Using a 3 oz cookie scoop, fill each muffin liner about two-thirds full with batter. Bake for 16-20 minutes or until a toothpick inserted in the center comes out clean.
Step 6: Let the cupcakes cool in the pan for 10 minutes, then transfer them to a wire rack to cool completely.
Step 7: For the peanut butter marshmallow filling, combine peanut butter, marshmallow fluff, milk, and cinnamon in a medium bowl. Once smooth, gradually mix in powdered sugar until the filling is pipeable. Transfer to a piping bag.
Step 8: Core the center of each cooled cupcake about two-thirds deep using a cupcake corer or a sharp knife. Fill the holes fully with the peanut butter filling and replace the tops.
Step 9: For the peanut butter buttercream, let the butter sit at room temperature for 30 minutes until slightly softened. Sift the powdered sugar while waiting.
Step 10: Beat the butter on medium speed until fluffy. Add peanut butter and beat for 2 minutes, scraping down the sides periodically for even mixing.
Step 11: Slowly add the powdered sugar and mix until combined. Add vanilla extract and cold heavy cream. Mix on low until incorporated, then beat on high for 3 minutes until fluffy. Chill in the fridge for 15 minutes to firm up.
Step 12: Pipe the buttercream generously onto each cupcake and top with a Reese’s peanut butter cup for decoration.

Tips & Variations

Use room temperature eggs and buttermilk to ensure a smooth batter and even baking.
For a nut-free variation, substitute the peanut butter filling and frosting with a chocolate or vanilla cream cheese filling.
Try adding a pinch of espresso powder to the batter to enhance the chocolate flavor.
If you prefer a firmer filling, reduce marshmallow fluff and add a bit more powdered sugar.

Storage

Store cupcakes in an airtight container in the refrigerator for up to 3 days. Let them come to room temperature before serving for the best texture and flavor. You can also freeze the cupcakes without frosting for up to 2 months; thaw overnight in the refrigerator and frost before serving.

How to Serve

The image shows a dark chocolate cupcake with three layers: the bottom layer is the cupcake itself, which is dark brown and textured with a paper liner; the middle layer is a swirl of light brown creamy frosting with fine ridges piped thickly on top; the top layer is a curved milk chocolate piece placed vertically into the frosting. Behind the cupcake, there are blurred elements including similar cupcakes and a white bottle, all set on a white marbled surface. Photo taken with an iphone --ar 4:5 --v 7

Serve this delicious recipe with your favorite sides.

FAQs

Can I make these cupcakes dairy-free?

Yes, substitute the buttermilk with a dairy-free milk plus a tablespoon of lemon juice or vinegar, use dairy-free butter, and choose a dairy-free marshmallow fluff and peanut butter frosting alternative.

How do I prevent the cupcakes from sinking in the middle?

Be careful not to overmix the batter and avoid opening the oven door during baking. Also, make sure your baking powder and baking soda are fresh.