1 1/4 c. flour
2 t. baking soda
2 t. baking powder
pinch kosher salt
1 1/4 c. sugar
4 oz. baking chocolate, chopped
1 stick butter, cut into pieces
2 t. vanilla
Place sugar and 1 c. water into a saucepan over med high heat. Bring to a boil, stirring until sugar dissolves. Pour into the large bowl of a stand mixer fitted with the paddle attachment. Add the chocolate and butter. Let sit, stirring occasionally until melted and slightly cooled. Stir in the vanilla. Beat the eggs into the mixture and then gradually add the dry ingredients at low speed until combined. Batter will be very thick and sticky. Divide evenly into 24 muffin tins lined with cupcake papers, about 1/4 c. batter per cupcake.
Bake in a preheated 350* oven for 20-25 minutes, until a toothpick inserted in the center removes cleanly. Cupcakes will be sunken in the middle. Don't panic. Cool in the pan for 25 minutes, transfer to a cooling rack and let cool completely.
For Marshmallow Creme Filling
4 T. butter, room temperature
1 c. powdered sugar
2 t. vanilla
3 T. heavy cream
1 (7 oz) jar of Marshmallow Creme
In small bowl of stand mixer, fitted with whisk attachment, cream butter until light and fluffy. Gradually add the powdered sugar until combined. Add vanilla and heavy cream. Beat in the Marshmallow creme until until smooth, light and fluffy. Refrigerate until ready to use.
6 oz. bittersweet chocolate
1/2 c. heavy cream
1 T. butter
1/4 t. vanilla
Place chocolate in a stainless steel bowl. Heat cream and butter in a small saucepan until nearly boiling. Pour over chocolate and let set for 5 minutes. Whisk until smooth and glossy then whisk in the vanilla. Allow to cool before frosting while still remaining liquid and glossy.
Fill a pastry bag fitted with a small star tip, with the marshmallow cream. Insert the tip into the center of each cupcake and fill until it feels heavier and a little of the cream is visible at the top.
Spread ganache over each cupcake filling the indentation and covering flat over the cupcake with a knife. Refrigerate for at least 15 minutes or until ganache is hardened.
Using leftover marshmallow creme, store bought icing or homemade icing and a pastry bag fitted with a small piping tip, create a swirly design along the top of each cupcake. Store in refrigerator until ready to serve.