For the filling:
1 ½ sticks soft unsalted butter
1 ¼ cups powdered sugar
½ tsp vanilla bean powder or paste
8 Campfire Regular Marshmallows
For the chocolate ganache topping:
1 cup dark chocolate chips
¼ cup heavy cream
¼ cup whole milk
Start by making a batch of your favorite easy chocolate cake. Distribute the batter evenly into 12 cupcake liners.
Preheat your oven to 350°F and bake for 25 to 30 minutes until an inserted toothpick comes out clean. Remove the cupcakes from the cupcake tray and allow them to cool to room temperature before filling them.
To make the filling: In the bowl of your stand mixer or hand mixer, add in your very soft butter, vanilla and half of the powdered sugar. Whisk on high for 5 to 10 minutes until white and pale in color and double in volume. Scrape down the sides of your bowl and whisk again for an additional 10 minutes—adding in the remaining half of your powdered sugar. Before adding in the marshmallows, remove a small amount of buttercream frosting to set aside and put into another piping bag to decorate the tops of the cupcakes.
In a microwave safe bowl, add in your marshmallows and microwave for 30 to 40 seconds. You will notice the marshmallows get bigger and puffy. Use a rubber spatula to mix them around. Ensure that they are not too hot and then add the melted marshmallows into your buttercream frosting. It may create an odd texture at first, but trust the process as this makes an incredible buttercream fluff filling.
Load your filling into a piping bag, press the piping bag into each cupcake to fill the center of each one. Try to distribute the filling evenly so each cupcake has a generous amount of filling. Set these aside at room temperature and clean off the tops of the cupcakes if a little buttercream frosting is left on the top.
In another microwave safe bowl, add in your chocolate chips, heavy cream and milk. Microwave for 45 seconds. Be sure to use high-quality dark chocolate for this step to ensure the best results. Whisk the chocolate mixture together to create a ganache which should be a smooth and shiny chocolate mixture. If it is a little bit too thick, add in a few more tablespoons of milk to loosen it up. Dunk in each cupcake upside down to coat the top and repeat this process twice for each cupcake for a generous coating. Allow the chocolate coating to set. You can place these in the refrigerator for 10 or 15 minutes to speed up the process. Once the chocolate coating is fully set, take your small piping bag of buttercream that you had set aside and pipe small swirls along the top.
Store these at room temperature for up to four days.
For the cupcake batter, you can use a box of your favorite chocolate cake mix to reduce the prep work.
