Guiness Cupcakes with Bailey's Frosting (Car Bomb Cupcakes)

UPDATE- So I updated this recipe a bit when I made a Guiness Cake this year for St. Patrick's Day. The cake recipe is a bit denser than this recipe, relying on baking powder more than baking soda to rise and with a little more chocolate. I also made the chocolate whiskey frosting.

Guiness cake is delicious. It can be made with any chocolate or dark stout beer, such as Duck Rabbit Milk Stout. There seem to be two main recipes for it online, Nigella Lawson's and the Great Barrington Brewery recipe. I have made both. These cupcakes I choose Nigella Lawson's, adapted it for cupcakes, and increased the darkness to it by adding a 1/4 cup of coffee in addition to the Guiness. However, while the recipe calls for a cream cheese frosting, I used the Bailey's Irish Cream Butter Cream recipe found on Smitten Kitchen. If you are asking, why did you not ALSO do the Chocolate Whiskey Ganache on Smitten Kitchen to truly make it a car bomb cupcake? The answer is two-fold. First, I didn't have a tiny baking round at my disposal, as this was made at my sister's house for my brother-in-law's birthday. Secondly, this cake is very rich and the Bailey's frosting is over the top and alcoholic as is. Last time I made the full-sized cake (using the Great Barrington recipe plus a little extra chocolate), I accused it (the cake) of getting me drunk. That might have been an unfair accusation given the wine consumed at that dinner party prior to the cake's arrival on the scene, but the point is the same. There's alcohol in the Bailey's and I think that's enough and that the whiskey ganache is unnecessary.

Unlike the Irish Cream, the Guiness alcohol does cook fully off, so if you want to serve this to kids, just do a basic cream cheese frosting instead. When I make this for St. Patrick's Day, I only top the top of the cake, making it look like a glass of Guiness with the foam on top. 

The superfine sugar is always nice to use in baking. If you don't have it, you can just use regular sugar, or if you are feeling fancy, run 2 cups of regular sugar through a food processor for a minute, creating a finer sugar. Remember that making frosting is not an exact science (unlike most else things in baking, so enjoy it). It will look wrong, then right, then wrong again. The trick is to add the powdered sugar in batches at a time to the creamed butter. This not only prevents a mess of powdered sugar everywhere, but also tends to require less sugar to hit your desired fluffy and delicious consistency.

Guiness Cupcakes with Bailey's Irish Cream Frosting (Car Bomb Cupcakes)

Guiness Cake:

Paper or Aluminum  muffin or cupcake wrappers
1 cup Guinness stout + 2 tablespoons
10 tablespoons (1 stick plus 2 tablespoons) unsalted butter
3/8 cup unsweetened dutch processed cocoa powder

1/4 cup cold coffee and/or 1 tsp espresso powder (both optional)
2 cups superfine sugar (I have used regular granulated sugar with no ill effects)
3/8 cup sour cream
2 extra-large eggs
1 tablespoon vanilla extract
2 cups all-purpose flour
2 1/2 teaspoons baking soda

Bailey's Frosting:

3 to 4 cups confections sugar
1 stick (1/2 cup or 4 ounces) unsalted butter, at room temperatue
3 to 4 tablespoons Baileys - 1 airplane bottle's worth

Additional milk or cream for blending if necessary

Instructions

For the Cupcakes

1. Heat oven to 350 degrees. 
2. Line muffin tins with foil or paper liners
3. In a large saucepan, combine Guinness and butter. Place over medium-low heat until butter JUST melts, then remove from heat into medium sized bowl. 
4. Add cocoa and superfine sugar, and whisk to blend.
5. Meanwhile, in a small bowl, combine sour cream, eggs and vanilla; mix well. 
6. Add sour cream and egg mixture to Guinness mixture.
7. Add coffee and espresso powder if using.
8. Add flour and baking soda, and whisk again until smooth. 
9. Pour into muffin tins, filling about 3/4 of the way, and bake until risen and a toothpick inserted in the center comes out clean, 17 to 20 minutes, rotating once for even baking. This may slightly deflate the cupcakes, so it might be good to have an official "tester" cupcake.
10. Leave in muffin tins for five minutes then remove to a wire rack to finish cooling. Do not frost until completely cool.

For the Frosting

1. Whip the butter in the bowl of an electric mixer, or with a hand mixer, for several minutes. You want to get it very light and fluffy. Slowly add the powdered sugar, a few tablespoons at a time.
2. When the frosting looks thick enough to spread or thicker, drizzle in the Baileys (or milk if you are doing the non-alcoholic option) and whip it until combined and frosting is correct texture. 
3. If this has made the frosting too thin (it shouldn’t, but just in case) beat in another spoonful or two of powdered sugar.
4. Frost the top of the cupcakes and serve. Store in a covered container in the fridge. They should keep for at least a day before starting to go stale.