Step 1

Preheat oven to 350°F. Line 12 cupcake tins with liners. Set aside.

Step 2

In a large mixing bowl, whisk together the cocoa, flour, sugar, baking powder, salt.

Step 3

In a separate bowl, whisk the oil, eggs, Guinness, sour cream, and vanilla extract together. Add the wet ingredients to the dry ingredients and whisk until smooth.

Step 4

Divide the batter evenly between the cupcake liners filling them about 3/4 of the ay up. Bake for 20-25 minutes. Remove from oven and allow to cool completely on a wire rack.

Step 5

While the cupcakes are cooling, make the frosting. In the bowl of a stand mixer fitted with the paddle attachment, combine the butter, cocoa powder, powdered sugar, Guiness, vanilla, and salt. Beat on low speed gradually increasing to high until light and fluffy.

Step 6

Frost the cupcakes by scooping the frosting into a piping bag with a large star tip. Swirl the frosting around the cupcake, starting from the middle and working your way outwards. Continue to spiral the frosting up like a pyramid until the cupcake is frosted. Sprinkle with flaked sea salt, if using, and serve!