Dark Chocolate Cupcakes with Marshmallow Filling

4.67 from 3 votes

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Dark Chocolate Cupcakes with a fluffy marshmallow filling and creamy chocolate frosting. These dangerously decadent cupcakes are sure to delight any chocolate lover.

By mixing the cocoa powder and bittersweet chocolate with the butter, rather than adding the cocoa to the dry ingredients, you end up with a cupcake that has a stronger and richer chocolate flavor.

This recipe does not double very well. If you want to make 24 cupcakes, it’s best to make two separate batches and bake each separately. This is one of my favorite chocolate cupcake recipes; in fact I made them a few months ago with peanut butter frosting that were incredible.

So when I had a special request from a coworker to make cupcakes for her son’s birthday I immediately thought of those Dark Chocolate Cupcakes with Peanut Butter Frosting. Her son was very specific in the type of cupcakes he desired and did not want the peanut butter frosting. He wanted the cupcakes to have a filling similar to Hostess cupcakes, topped with chocolate frosting and sprinkles. The marshmallow filling in these cupcakes are fantastic and a wonderful surprise to those not expecting it. She said that these cupcakes were a huge hit and her son even tried to convince her that he needed to have one of these for breakfast on his birthday as well! 🙂

Ingredients:

For the Cupcakes:

8 tablespoons unsalted butter, cut into 4 pieces

2 ounces bittersweet chocolate, chopped

1/2 cup Dutch-processed cocoa powder

3/4 cup all-purpose flour

1/2 teaspoon baking soda

3/4 teaspoon baking powder

2 eggs

3/4 cup granulated sugar

1 teaspoon vanilla extract

1/2 teaspoon table salt

1/2 cup sour cream

For the Marshmallow Filling:

6 tablespoons unsalted butter, softened

1 ½ cups confectioners’ sugar

¾ cup Marshmallow Fluff

1 ½ tablespoon heavy cream

For the Creamy Chocolate Frosting:

1/3 cup (2 1/3 ounces) granulated sugar

2 large egg whites

pinch table salt

12 tablespoons (1 1/2 sticks) unsalted butter, softened and cut into tablespoon pieces

6 ounces bittersweet chocolate, melted and cooled to 85-100 degrees

1/2 teaspoon vanilla extract

How to make Dark Chocolate Cupcakes with Marshmallow Filling:

Step 1. Adjust oven rack to lower-middle position and preheat to 350 degrees F. Line muffin pan with baking cup liners.

Step 2. In a medium heatproof bowl, combine butter, chocolate, and cocoa. Set bowl over saucepan containing barely simmering water; heat mixture until butter and chocolate are melted and whisk until smooth and combined. Set aside and cool until just warm to the touch.

Step 3. In a small bowl, whisk flour, baking soda, and baking powder; set aside.

Step 4. In a medium bowl, whisk eggs; add sugar, vanilla, and salt until fully incorporated. Add cooled chocolate mixture and whisk until combined. Sift one-third of flour mixture over chocolate mixture and whisk until combined; whisk in sour cream until combined. Sift remaining flour mixture over chocolate mixture and whisk until batter is combined.

Step 5. Divide the batter evenly among muffin pan cups. Bake 18 to 20 minutes or until toothpick inserted into center of cupcakes comes out clean.

Step 6. Cool cupcakes in muffin pan on wire rack for 15 minutes. Carefully lift each cupcake from muffin pan and set on wire rack. Cool to room temperature.

Step 7. To make the marshmallow filling: in a medium bowl beat together the butter, confectioners’ sugar, Marshmallow Fluff and 1 ½ tablespoons of the heavy cream on medium speed until fluffy. Transfer to a pastry bag fitted with a ¼ – inch plain round tip.

Step 8. Once cupcakes have cooled, use a paring knife or apple corer to cut out a small circle in the center of each cupcake.

Step 9. Remove the core and trim leaving the core just big enough to be used to plug the hole once it is filled.

Step 10. Pipe the marshmallow filling into each hollowed cupcake.

Step 11. Once the filling is in place, place the trimmed core of the cupcake back into place.

Step 12. To make the frosting: combine the sugar, egg whites, and salt in the bowl of a stand mixer. Set over a small saucepan of simmering water, and whisking constantly, cook until the mixture is slightly thickened, foamy, and registers 150 degrees on an instant read thermometer, 2-4 minutes.

Step 13. Attach bowl to the stand mixer and fit the whisk attachment, beat at medium speed, until mixture is the consistency of shaving cream and slightly cooled, 1-3 minutes. Add butter 1 piece at a time, until smooth and creamy.

Step 14. Once all the butter as been added, pour in the cooled chocolate and vanilla. Mix until well combined. Increase speed to medium-high and until light and fluffy, another 30 seconds to a minute.

Pipe frosting onto cooled cupcakes.

Enjoy!

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Dark Chocolate Cupcakes with Marshmallow Filling

Servings:

Dark Chocolate Cupcakes with a fluffy marshmallow filling and creamy chocolate frosting. These dangerously decadent cupcakes are sure to delight any chocolate lover.

Dark Chocolate Cupcakes with Marshmallow Filling

4.67 from 3 votes

Review Recipe

Ingredients

For the Cupcakes:

8 tablespoons unsalted butter, cut into 4 pieces
2 ounces bittersweet chocolate, chopped
1/2 cup Dutch-processed cocoa powder
3/4 cup all-purpose flour
1/2 teaspoon baking soda
3/4 teaspoon baking powder
2 eggs
3/4 cup granulated sugar
1 teaspoon vanilla extract
1/2 teaspoon table salt
1/2 cup sour cream

For the Marshmallow Filling:

6 tablespoons unsalted butter, softened
1 ½ cups confectioners’ sugar
¾ cup Marshmallow Fluff
1 ½ tablespoon heavy cream

For the Creamy Chocolate Frosting:

1/3 cup 2 1/3 ounces granulated sugar
2 large egg whites
pinch table salt
12 tablespoons 1 1/2 sticks unsalted butter, softened and cut into tablespoon pieces
6 ounces bittersweet chocolate, melted and cooled to 85-100 degrees
1/2 teaspoon vanilla extract

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Instructions

Adjust oven rack to lower-middle position and preheat to 350 degrees F. Line muffin pan with baking cup liners.
In a medium heatproof bowl, combine butter, chocolate, and cocoa. Set bowl over saucepan containing barely simmering water; heat mixture until butter and chocolate are melted and whisk until smooth and combined. Set aside and cool until just warm to the touch.
In a small bowl, whisk flour, baking soda, and baking powder; set aside.
In a medium bowl, whisk eggs; add sugar, vanilla, and salt until fully incorporated. Add cooled chocolate mixture and whisk until combined. Sift one-third of flour mixture over chocolate mixture and whisk until combined; whisk in sour cream until combined. Sift remaining flour mixture over chocolate mixture and whisk until batter is combined.
Divide the batter evenly among muffin pan cups. Bake 18 to 20 minutes or until toothpick inserted into center of cupcakes comes out clean.
Cool cupcakes in muffin pan on wire rack for 15 minutes. Carefully lift each cupcake from muffin pan and set on wire rack. Cool to room temperature.
To make the marshmallow filling: in a medium bowl beat together the butter, confectioners’ sugar, Marshmallow Fluff and 1 ½ tablespoons of the heavy cream on medium speed until fluffy. Transfer to a pastry bag fitted with a ¼ – inch plain round tip.
Once cupcakes have cooled, use a paring knife or apple corer to cut out a small circle in the center of each cupcake.
Remove the core and trim leaving the core just big enough to be used to plug the hole once it is filled.
Pipe the marshmallow filling into each hollowed cupcake.
Once the filling is in place, place the trimmed core of the cupcake back into place.
To make the frosting: combine the sugar, egg whites, and salt in the bowl of a stand mixer. Set over a small saucepan of simmering water, and whisking constantly, cook until the mixture is slightly thickened, foamy, and registers 150 degrees on an instant read thermometer, 2-4 minutes.
Attach bowl to the stand mixer and fit the whisk attachment, beat at medium speed, until mixture is the consistency of shaving cream and slightly cooled, 1-3 minutes. Add butter 1 piece at a time, until smooth and creamy.
Once all the butter as been added, pour in the cooled chocolate and vanilla. Mix until well combined. Increase speed to medium-high and until light and fluffy, another 30 seconds to a minute.
Pipe frosting onto cooled cupcakes.