Chocolate Marshmallow Cupcakes

For the marshmallow frosting: 

4 large egg whites

1 cup of sugar

1/4 tsp. cream of tartar

1 tsp. vanilla extract

For the ganache: 

5 oz. bittersweet chocolate, chopped 

1/2 cup heavy cream

1/2 tsp. vanilla extract

For the cake, sift together the cocoa, flour, salt, baking powder and baking soda into a bowl. In an electric mixer, beat together the butter and sugar until smooth and creamy, about 5 minutes. Add the eggs one at a time, making sure they are fully incorporated. Be sure to scrape down the sides of the bowl. Mix together the coffee and milk. Add half of the flour mixture, then the coffee-milk mixture, then the rest of the flour mixture until well combined. Pour into pre-lined cupcake pans about 3/4 full. Bake for about 15 - 20 minutes or until an inserted toothpick comes out clean.

For the frosting, place the whites, sugar and tartar into the bowl of an electric mixer. Set over a pot of simmering water and whisk constantly until sugar has dissolved and the eggs are warm to the touch. Transfer the bowl back to the machine and whisk, starting on low speed then eventually moving to high speed. Whisk until glossy peaks form, about 5 - 7 minutes. Add vanilla, mix until combined. Now frost your cupcakes! You can spoon the mixture on or use any tip you like. You can also either broil the cupcakes to toast the marshmallow or use a blow torch (which I used).