Chocolate cake with cream filling

Ingredients:

• 1 package (430 g) of Devil's Food biscuit mix (+ all necessary additional ingredients)
• 6 tbsp unsalted butter at room temperature + 2 tbsp unsalted butter
• 1 cup marshmallow cream
• 1.5 cups powdered sugar
• 1/3 cup + 1 tbsp heavy cream
• 100 g semi-sweet chocolate chips
• Special equipment: a 12-cup round cake pan with a hole in the center and a pastry bag fitted with a long round tip

Preparation:

1. Prepare the pan according to the instructions on the cake mix package. Bake the Devil's Food cake according to the package instructions. Let cool completely.
2. Combine the softened butter and marshmallow cream in a large bowl and beat with a mixer until smooth. Add the powdered sugar and 1 tablespoon of heavy cream and beat until fluffy, about 3 minutes. Transfer the cream to a pastry bag fitted with a long, thin, round tip.
3. Turn the cake over so it's flat side up and use a wooden skewer to make 12 evenly spaced holes, pressing only halfway into the cake and gently wiggling the skewer to widen the holes until a cavity about 2 cm wide forms inside. Insert the tip of a pastry bag into each hole and pipe a small amount of frosting until it begins to ooze out of the hole, reserving about 1/4 cup of frosting for decorating the cake. Turn the cake over so it's flat side down and place it on a cake stand or serving platter.
4. Place the chocolate chips in a small heatproof bowl. In a small saucepan, heat the remaining 1/3 cup of cream until just barely simmering, then pour it over the chocolate. Stir until the chocolate is melted, then add the remaining 2 tablespoons of butter. Drizzle the ganache over the cake and let it set for about 30 minutes. Pipe the cream on top in pretty curls. Serve the cake immediately or cover and refrigerate for up to 2 days..