Espresso Cupcakes with White Chocolate Frosting
Decadent is the only way to describe these cupcakes. The rich, mocha cake is filled with even richer chocolate ganache, then, as if that weren't enough, they're topped off with white chocolate frosting.
For the milk chocolate ganache
For the white chocolate frosting
Make the cupcakes
Preheat the oven to 350°F (175°C). Line 12 cupcake wells with paper liners.
Sift together the flour, baking soda, baking powder, and salt. Stir in the espresso powder.
Using an electric mixer on medium speed, beat the butter with the granulated sugar until light, 1 minute with a stand mixer or 2 minutes with a handheld mixer. Add the eggs, one at a time, beating well after each addition. Continue to beat the mixture for 1 minute with a stand mixer or 2 minutes with a handheld mixer. On low speed, alternately add the dry ingredients and the milk in 2 additions, stirring until incorporated after each addition.
Pour the batter into the paper-lined cupcake wells. Bake until a skewer inserted in the middle comes out clean, about 20 minutes. Let cool to room temperature, then remove from the pans.
Make the ganache
Place the cream in a small, heavy-bottomed saucepan and warm over medium-high heat until it begins to bubble around the edges, about 5 minutes. Remove the pan from the stove, add the chocolate, and whisk until smooth. Transfer to a bowl and place plastic wrap directly over the ganache. Refrigerate until cold.
Make the frosting
Melt the white chocolate in a double boiler (see note below). Stir until smooth. Let cool to room temperature.
Sift the confectioners' sugar into a medium bowl. Stir in the milk and vanilla. Add the butter and salt and beat until smooth. Stir in the cooled white chocolate. Refrigerate until firm enough to frost the cupcakes, about 30 minutes.
Cut out about one quarter of the inside of each cupcake with a small paring knife. Fill the indent with the milk chocolate ganache. Frost each cupcake with the white chocolate frosting.
The cupcakes can be made a day in advance; wrap in plastic wrap and store at room temperature. The ganache can be made several days ahead and kept refrigerated. The frosting can be made a day ahead and stored at room temperature. For maximum flavor and moistness, fill and frost the cupcakes the day you plan to serve them.
Bring a pot one-third full of water to a boil. Turn off the heat and place a stainless steel bowl over the water (you can also use a double boiler). Make sure the bowl is sitting over, not in, the water, as chocolate will scorch if it gets too hot. (To check this, place the bowl on the pot and then pick it up to see if there is any water on the bottom of the bowl). The residual heat will melt the chocolate. While the chocolate is melting, stir occasionally. If you haven’t stirred the chocolate while it was melting, it may look unmelted on top, but the rest of it could be melted. This is especially important with milk and white chocolates since they scorch easily.