Yield: 24 servings
CAKE:
1 ½ sticks unsalted butter, softened
1 ½ cups all-purpose flour
1 cup cake flour
1 teaspoon baking powder
1 teaspoon baking soda
1 teaspoon cinnamon
½ teaspoon salt
1 ½ cups sugar
3 eggs, room temperature
2 teaspoons pure vanilla extract
1 cup sour cream
FROSTING:
5 sticks unsalted butter, softened
5 oz. bittersweet chocolate, melted and cooled
5 oz. white chocolate, melted and cooled
1 lb. confectioners’ sugar, sifted
¼ cup heavy cream
1 teaspoon pure vanilla extract
1 teaspoon cinnamon
1 teaspoon ancho chile powder
½ teaspoon cayenne pepper
Preheat oven to 350°F. Line muffin pans with paper baking cups.
In a medium bowl, whisk the all-purpose flour with the cake flour, baking soda, baking powder, cinnamon and salt. In a separate bowl (or stand mixer), beat the butter with the sugar at medium speed until fluffy,
about 3 minutes. Beat in the eggs and vanilla until
incorporated. Add the dry ingredients slowly and then the sour cream.
Distribute batter evenly into the paper cups. Bake on middle rack in oven for 15 minutes, or until cupcakes are springy. Transfer to cooling racks and let cool
completely before frosting.
Frosting: Beat softened butter until creamy. Add
confectioner’s sugar on low speed until incorporated, then on high speed until fluffy, about 2 minutes.
Switch back to low speed and add in cream, vanilla, cinnamon, ancho chile powder and cayenne, then
gradually beat in the bittersweet and white chocolate.
Increase speed and beat until light. Stir with a wooden spoon to deflate air bubbles if necessary.