• Preheat oven to 350℉. Line two 12-cup or one 24-cup muffin pans with cupcake liners.

Cupcake base

• Add the cake flour, cocoa powder, baking soda and salt to a small bowl. Mix well and set aside.
• Add the butter and sugar to the mixing bowl. Mix on low until fully incorporated.
• Add the eggs, one at a time, to the mixing bowl. Mix on low until incorporated.
• Alternate adding half of the flour mix and half of the buttermilk. Mix on low until incorporated.
• Use a large 4 tablespoon cookie scoop to fill each muffin tin.
• Bake for 18-19 minutes, or until a toothpick comes out clean. [If you are using two 12 cup muffin pans on different oven racks, rotate pans halfway through.]
• Let the cupcakes cool for 5-10 minutes. Pour the Bailey's Irish Cream into a small bowl. With a pastry brush, lightly brush the tops of each cupcake with the Baileys. Brush each cupcake twice. Move the cupcakes to a cooling rack to cool completely.

Frosting

• Add the room temperautre butter to a mixing bowl and mix on medium speed until creamy, about 1-2 minutes.
• Add the powdered sugar and three tablespoons of Baileys to the mixing bowl. Mix on medium high until light and fluffy, scraping down the sides several times, about 7-8 minutes. [Depending on the temperature of the butter and the humidity of the kitchen, you may need to add an additional tablespoon of Baileys or heavy cream if the frosting is too heavy/thick.]
• Add the frosting to the cupcakes by using an icing (offset) spatula, a regular knife or by piping it on.
• Optional: top with chocolate shavings. To make chocolate shavings, use a vegetable peeler or a chocolate shaver to peel small pieces off the side of a semi sweet chocolate bar. (Handle the shavings minimally and quickly to avoid melting.)