for the chocolate cupcakes
4 1/2 ounces high-quality bittersweet chocolate, finely chopped
9 tablespoons (1 stick plus 1 tablespoon) unsalted butter, room temperature
1 cup confectioners’ sugar
6 large eggs, separated, at room temperature
1 teaspoon vanilla extract
1/2 cup granulated sugar
1 cup all-purpose flour
for the frosting
2 sticks (1 cup) unsalted butter, room temperature
2 teaspoons pure vanilla extract
1/8 teaspoon fine sea salt
1/3 cup malt powder
1/3 cup unsweetened cocoa powder
2 1/2 cups confectioners’ sugar (powdered sugar)
3-5 tablespoons heavy cream
Preheat oven to 400F. Prepare a muffin pan with liners.
In the top part of a double boiler over very hot, but not simmering water, or in a microwave at medium power, melt the chocolate. Remove from the heat or the oven, and let stand, stirring often, until cool. Beat the butter in the bowl of a stand mixer fitted with the paddle blade on medium-high speed until smooth, about 1 minute. On low speed, beat in the confectioners’ sugar. Return the speed to medium-high and beat until light in color and texture, about 2 minutes. Beat in the egg yolks, one at a time, scraping down the sides of the bowl. Beat in the chocolate and vanilla. Beat the egg whites and granulated sugar in a large bowl with an electric mixer on high speed just until they form soft, shiny peaks. Do not overbeat. Stir about one fourth of the beaten whites into the chocolate mixture to lighten it, and then fold in the remaining whites, leaving a few visible wisps of whites. Sift half of the flour over the chocolate mixture, and fold in with a rubber spatula. Repeat with the remaining flour.
Fill the lined muffin cups three-quarters full, being careful not to overfill. Bake until a toothpick inserted in the center of the cupcake comes out clean, about 20-22 minutes. Cool the cupcakes in the pan for 5 minutes, then transfer to a wire rack to cool completely.
To make your frosting, in the work bowl of a stand mixer fitted with the paddle attachment, beat butter, vanilla, and salt on medium speed until creamy. In a large bowl, sift together the malt powder, cocoa powder and confectioners’ sugar. Gradually add the dry ingredients to the butter and mix at low speed until fully incorporated. Scrape down the sides of the bowl as needed. Once all of the dry ingredients have been incorporated, add in 3 tablespoons of heavy cream. Turn the mixer up to medium speed and beat the butter cream for about 5 minutes, scraping down the sides of the bowl as needed. If you want your frosting a little thinner, gradually add in more cream, 1 teaspoon at a time until you reach the desired consistency. 5. Frost your cooled cupcakes and garnish with Whoppers/Maltesers and a paper straw to make it look like a milkshake.