1- Preheat oven to 375 degrees and line 24 muffin tins with cupcake liners.
- In a medium-sized bowl, whisk together flour, baking powder, and salt.
- In the bowl of an electric mixer, beat together the butter and sugar until light and fluffy, about 2-3 minutes.
- Add eggs, beating after each addition then add the vanilla and zest.
- Combine milk and beer and alternatively add this mixture and the flour mixture to the butter/sugar mixture with the mixer on low speed, starting and ending with the flour.
- Fill the cupcake liners 2/3 full and bake for 18 minutes, or until cake tester comes out clean.
- When cupcakes are done, poke holes in the tops of the cupcakes with toothpicks and brush some beer on each while still warm.
2- Cream together the cream cheese and butter in an electric mixer until smooth and creamy, about 2-3 minutes.
- Add the citrus juice and zest and gradually add the powdered sugar until well-combined. Beat until smooth for about 2 minutes.
- Load frosting in a piping bag fit with a large star tip and pipe cupcake tops once cooled.