Yet another wonderful recipe from my Ad Hoc cookbook (Thank you, Brian Troy!) Rich and moist with a very light egg-white based icing; this is is the best recipe I've found so far for Devil's Food Cupcakes!
(For the Cupcakes:)
1 2/3 cups cake flour
1/2 cup plus 1 tablespoon unsweetened alkalized cocoa powder (I like Trader Joe's Cocoa for an affordable option)
1 teaspoon baking powder
1 teaspoon baking soda
1 1/2 cups granulated sugar
1/2 teaspoon kosher salt
1 cup buttermilk
1 cup sour cream
3 large eggs, lightly beaten
6 tablespoons (3 ounces) unsalted butter, melted
Semisweet chocolate shavings (optional...but SO worth it)
(For the Chocolate Buttercream Frosting)
1 3/4 cups plus 2 tablespoons granulated sugar
3/4 cup egg whites (from about 6 large eggs)
3 1/2 sticks (14 ounces) unsalted butter, cut into 1/2-inch pieces, at room temperature
5 ounces 61 to 64% chocolate, melted and cooled (I recommend using a double-boiler or metal bowl over a pot of boiling water)
Preheat the oven to 350 degrees F. Line 24 cupcake cups with paper liners.
Sift the cake flour, cocoa powder, baking powder, baking soda, and sugar into the bowl of a stand mixer (or if you are like me and are still dreaming of getting that KitchenAid Mixer, use a large bowl and a hand-mixer). Stir in the salt. If you are using a stand mixer, place the bowl on the mixer stand and fit the mixer with the paddle.
Combine the buttermilk and sour cream in a large measuring cup or a bowl. Stir the eggs and melted butter together in a bowl. Stir the eggs and melted butter together in a bowl.
With the mixer on medium-low speed, add the buttermilk and egg mixtures alternately, scraping down the sides often to prevent any lumps in the mixture.
Divide the batter among the lined cupcake cups. Bake for 10 minutes. Rotate the pan and bake for another 10 minutes, or until a cake tester or a wooden skewer inserted in the center of a cupcake come out clean. Remove the cupcakes from the tins and let cool to room temperature on a cooling rack.
(To make the Buttercream Frosting:)
Fill a medium saucepan halfway with water and bring to a simmer over medium heat. Combine the sugar and egg whites in the bowl of a stand mixer, set over the simmering water, and whisk constantly until the sugar has dissolved and the misture is hot to the touch (150 degrees F to 160 degrees F).
Remove the bowl from the heat, immediately place on the mixer stand, and, using the whisk attachment, whip on high speed until the whites are thick and hold stiff peaks and the whites and the bowl are cool to touch, 10 to 12 minutes.
Switch to the paddle attachment. Beating on medium speed, add the butter 2 or 3 pieces at a time, being sure each batch is incorporated before adding more. If at any point the mixture looks broken, increase the speed to medium-high and beat to bring it back together, then reduce the speed and continue adding the butter.
Switch to the paddle attachment. Beating on medium speed, add the butter 2 or 3 pieces at a time, being sure each batch is incorporated before adding more. If at any point th mixture looks broken, increase the speed to medium-high and beat to bring it back together, then reduce the speed and continue adding the butter.
Once all of the butter has been added, check the consistency. If the frosting is too thin to hold its shape, beat for a few more minutes to thicken. Turn the mixer speed to low and add the melted chocolate.
Use a pastry bag fitted with a star tip to pipe rosettes of buttercream on top of the cupcakes, or simply spread the frosting with a small palette knife or icing spatula. Garnish with the chocolate shavings, if using.
The cupcakes are best frosted and eaten the day they are baked, but they can refrigerated for up to 2 days; bring to room temperature before serving.