Surprisingly these are not too boozy tasting. The Guinness in the cupcake batter enhances the flavor of the chocolate, similar to the way adding coffee would. These cupcakes have great flavor on their own. Make just the cupcake batter and top with your favorite frosting. You can pick up the flavor of the whiskey and Baileys in the chocolate filling and frosting but not in a bad way. If you are not into the boozy part of these cupcakes, substitute the Baileys with milk and don't add the whiskey. Happy St. Patty's day! For the cupcakes: 1 cup Guinness stout 1 cup unsalted butter, at room temperature 3/4 cup Dutch-process cocoa powder 2 cups all-purpose flour 2 cups granulated sugar 1 1/2 teaspoons baking soda 3/4 teaspoons salt 2 eggs 2/3 cups sour cream To make the cupcakes: Preheat the oven to 350F. Line 24 cupcake cups with liners. In a small saucepan, bring the Guinness and butter to a simmer over medium heat. Remove from the heat and add the cocoa powder and whisk until the mixture is smooth. Set aside to cool.In a medium bowl, whisk the flour, sugar, baking soda and salt to combine. In the bowl of a stand mixer, with a paddle attachment, beat the sour cream and eggs until combined. Add the Guinness-chocolate mixture to the egg mixture and beat to combine. With the mixture on low speed, add the flour mixture, beating until just combined. Divide the batter among the cupcake liners, using a 1/3 cup measuring cup. Bake for about 17 minutes and cool on a rack. For the whiskey ganache filling: 6 ounces bittersweet chocolate 2 ounces unsweetened chocolate 2/3 cup heavy cream 2 tablespoons unsalted butter, at room temperature 1 tablespoon Irish whiskey To make the ganache filling:.Finely chop the chocolate and transfer it to a medium bowl. Heat the cream in the microwave for 1-2 minutes, just until bubbles form around the edge of the measuring cup. Pour the cream over the chocolate and let it sit for one minute and then stir it until smooth. Add the butter and whiskey and stir until well combined. Let the ganache cool until thick but still soft enough to be piped.To fill the cupcakes, cut the centers of the cupcakes out, to make a 1-inch circle that is 2/3 deep. Fill a sandwich bag with the cooled ganache and snip one corner of the bag to pipe into the cupcake holes. For the Baileys frosting: 1 stick unsalted butter 2-3 cups powdered sugar 3 tablespoons Baileys Irish Cream To make the Baileys frosting:.Using the whisk attachment of a stand mixer, whip the butter on medium-high speed for 3 minutes, scraping the sides of the bowl occasionally. Reduce the speed to medium-low and gradually add the powdered sugar. Add the baileys, increasing the speed to medium-high and whip for another 2 minutes, until it is light and fluffy.