Prep Time: approximately 25 minutes.
1. Preheat the oven to 350
2. Line a muffin tin with cupcake liners.
3. Combine the Guinness and the butter, chopped into 1-inch chunks, in a large sauce pan, and heat to melt the butter.
4. Remove from heat
5. Whisk in the cocoa and sugar.
6. In a bowl, whisk the sour cream and the eggs and vanilla, then add to the beer mixture.
7. Sift together the flour and baking soda, and fold in the batter.
8. Pour into muffin molds and bake for 25 minutes, or until inserted cake tester comes out clean.
9. Let stand 10 minutes
10. Remove from muffin tin, and cool completely on a rack.
11. Topping:
- Allow butter to reach nearly room temperature then cream at high speed with an electric mixer.
- Add in milk and 1 cup of the powdered sugar to create a wet and thick mixture. (More or less powdered sugar may be required to reach desired consistency.)
- Add in the remaining liquids and mix until frosting is spreadable.
