Guinness Cupcakes With Bailey's Frosting

INGREDIENTS

• 1 cup unsalted butter
• 1 cup Guinness stout
• 2/3 cup Dutch-processed cocoa powder, sifted
• 1 cup light brown sugar
• 1 teaspoon table salt
• 2 cups all-purpose flour
• 1 cup white sugar
• 1 1/4 teaspoons baking soda
• 2 eggs
• 1/2 cup sour cream
• 1/2 cup unsalted butter
• 4 cups confectioners' sugar
• 1 pinch table salt
• 3 tablespoons irish cream (Bailey's or Carolan's)
• 1 tablespoon milk
• green sprinkles