Preheat oven to 350 degrees. Place your cupcake liners into your cupcake pan and set aside.
In a large bowl, add in the flour, sugar, cocoa powder, baking soda and baking powder. Whisk to combine the ingredients thoroughly.
In a separate large mixing bowl, add in the beer, vegetable oil, beaten eggs, vanilla bean paste and sour cream. Whisk until it comes together and is smooth. If you don't have vanilla bean paste, you can use the same amount of extract. It should use one full beer.
Add the dry ingredients into the wet ingredients and whisk to get most or all of the lumps out. My batter still had a few lumps in it that I couldn't get out. Be sure to scrape the edges and incorporate all of the flour.
Scoop the batter into the cupcake liners with an ice cream scoop. I filled my liners 3/4 full. The batter will be runny.
Place into the prepared oven and let bake for 17 minutes or until done. Place a toothpick into the center of the cupcake and if it comes out with moist crumbs or clean, they're done.
Let cool completely and start working on the frosting.
In a mixing bowl, add in the cream cheese and butter. Mix until light and fluffy. This will take about 2 minutes.
Add in the powdered sugar and Baileys and mix until incorporated. Turn the mixer on high and beat for another 2 minutes until the frosting is fluffy.
Add the frosting into a piping bag with a straight tip and pipe swirls on the cooled cupcakes.
Add the nonpareils to the frosting.
If you plan on frosting your cupcakes generously like I did mine, I would recommend doubling the frosting recipe.
Chocolate Guinness Cupcakes with Baileys Cream Cheese Frosting https://www.cookiedoughandovenmitt.com/chocolate-guinness-cupcakes-with-baileys-cream-cheese-frosting-3/