Edible Obsessions: Sweet Potato Cupcakes with Toasted Marshmallow Frosting

Cupcake Ingredients:

2 cups of all-purpose flour
2 tsp of baking powder
1/2 tsp of baking soda
1/4 tsp of salt
1 tsp of ground cinnamon
16 tbsp of unsalted butter, softened
1 1/2 cups of sugar
3 large eggs
17 oz of sweet potato puree
1/2 tsp of vanilla extract

Frosting Ingredients:

8 large egg whites
2 cups of sugar
1/2 tsp of cream of tartar
2 tsp vanilla extract

Directions:

Preheat the oven to 350° F.  Line two cupcake pans with paper liners.  In a medium bowl combine the flour, baking powder, baking soda, salt and cinnamon; stir together with a fork and set aside.  In the bowl of an electric mixer fitted with the paddle attachment, cream together the butter and sugar on medium-high speed until light and fluffy, about 2 minutes.  Beat in the eggs one at a time, scraping down the bowl after each addition.  Mix in the sweet potatoes and vanilla extract, beating just until combined.  Reduce the mixer speed to low and add the dry ingredients, mixing just until incorporated.

Divide the batter evenly between the prepared cupcake liners.  Bake for about 18-20 minutes, or until a toothpick inserted in the center comes out clean.  Let cool in the pan for 5-10 minutes, then transfer to a wire rack to cool completely.

To make the frosting, combine the egg whites, sugar and cream of tartar in the top of a double boiler. Heat the mixture, whisking frequently, until it reaches 160° F with an instant-read thermometer. Transfer the mixture to the bowl of an electric mixer fitted with the whisk attachment. Whisk starting at low speed and gradually increasing to medium-high speed until stiff, glossy peaks form. Mix in the vanilla until combined. Frost cooled cupcakes as desired. Brown with a kitchen torch and garnish with a sprinkle of brown sugar, if desired.