-
1
Preheat oven to 350 degrees with a rack in the upper and lower thirds. Fill two 12-cup cupcake pans with paper liners.
-
2
In a saucepan, heat the butter, stout, cocoa powder, and brown sugar, whisking often, until the butter is melted and mixture is smooth. Remove from heat and cool to room temperature.
-
3
Into the bowl of a stand mixer fitted with the paddle attachment, combine flour, granulated sugar, baking soda, and salt.
-
4
Add cooled Guinness mixture and beat on medium for 1 minute.
-
5
Add eggs and sour cream and beat on medium for 2 minutes, scraping down the bowl as necessary, until smooth.
-
6
Divide batter evenly among cupcake liners, filling about 2/3 full. Transfer to oven and bake 20-25 minutes, rotating halfway through, until a toothpick inserted into the center of a cake comes out clean.
-
7
Cool in pan 10 minutes, then remove and transfer to a cooling rack until completely cooled.
-
8
Meanwhile, in bowl of stand mixer fitted with the paddle attachment, cream butter until light and fluffy.
-
9
Add salt, and slowly add confectioners sugar.
-
10
Add 6 tablespoons Irish Cream and milk, adding more milk as necessary, until spreadable consistency is achieved.
-
11
Transfer to a piping bag or ziplock fitted with a star tip and wash stand mixer bowl.
-
12
In bowl of stand mixer fitted with the whisk attachment, whip cream until stiff peaks form.
-
13
Add remaining 2 tablespoons Irish cream and a pinch of salt and whisk to combine.
-
14
Transfer to a pastry bag fitted with a 1/2-inch pastry tip.
-
15
Insert tip into tops of cupcakes and divide whipped cream mixture evenly among cupcakes, dispensing approximately 1 tablespoon per cupcake.
-
16
Frost tops of cupcakes with Bailey's frosting and sprinkle with green sprinkles. Serve.
