Note: I originally found the recipe on Smitten Kitchen but have since adapted it a little based on my own preference. The Smitten Kitchen recipe is also GREAT though!
For the cupcakes:
- 1 cup stout
- 1 cup (2 sticks) unsalted butter
- 3/4 cup unsweetened cocoa powder
- 2 cups flour
- 2 cups sugar
- 1 1/2 teaspoons baking soda
- 1/2 teaspoon salt
- 2 large eggs
- 2/3 cup sour cream (full fat is best)
- 1/4 cup buttermilk
- For the filling:
- 8 ounces bittersweet chocolate
- 1/3 cup heavy cream
- 1/3 cup Bailey's Irish Cream
- 2 tablespoons butter, room temperature
- 1 to 2 teaspoons Irish whiskey
- For the frosting
- Note: If you want lots of frosting on each cake, go ahead and double this recipe – I did!
- 3 to 4 cups confections' sugar
- 1 stick (1/2 cup) unsalted butter, at room temperature
- 3 to 4 tablespoons Bailey's Irish Cream (or more, to taste) Since I doubled I used about 3tbsp bailey’s and 3 tbsp heavy cream since I had that left over
- Splash of vanilla & a splash of rum extract– why not? I live on the edge.
Get ready: pre-heat oven to 350°F. Line 24 cupcake cups with liners.
Bring 1 cup stout and 1 cup butter to simmer in heavy large saucepan over medium heat. Add cocoa powder and whisk until mixture is smooth. Remove from heat. Let cool a bit. I found that putting the pot into a shallow pan of cold water helped the cooling process.
In a separate large bowl, whisk flour, sugar, baking soda, and 3/4 teaspoon salt.
In another large bowl, using an electric mixer, beat eggs and sour cream in another large bowl to blend. Add stout-chocolate mixture to egg mixture and beat just until combined. WARNING! – if you haven’t let the stoudt cool to a luke-warm it will cook the eggs when you add it here and you don’t want that!
Add the dry mixture and beat briefly on slow speed. Using a rubber spatula, fold batter until completely combined.
Divide batter among cupcake liners, filling them 2/3 to 3/4 of the way. I found that I had enough batter for EXACTLY 24 cupcakes. Bake cake until tester inserted into center comes out clean, rotating them once front to back if your oven bakes unevenly. Cool 17-20 minutes. Cool cupcakes completely.
While your cupcakes cool, make the filling! Chop the chocolate into coarse but roughly even pieces, and transfer it to a heatproof bowl. Heat the cream until it is simmering (but not boiling) and pour it over the chocolate. Let it sit for about a minute and then stir until smooth. If this has not sufficiently melted the chocolate, you can put it on a double-boiler or give it 20 seconds in the microwave to help the chocolate get sufficiently melty. And honestly – who uses a double-boiler anymore?! WTF?! Add the butter, Irish Cream, and whiskey and stir until combined. You might need to stick it back in the microwave 10-15 second if the butter doesn’t melt all the way. Take a nip of the whiskey – you’ve got a while to go!
Make space for the filling. The original recipe suggests using an apple corer to cut out a section from your cooled cupcakes to fill, but lacking one I found that the cake is sturdy enough that if you gently cut out a circle using a small, sharp knife, it works just fine. I used a grapefruit section knife. You want to cut halfway to 2/3 of the way down.
Fill the cupcakes. NOTE: I like to do this when the filling has thickened a little – about 15-30 min in the fridge will help – stir it every 10 min. You can pipe in the filling, or if it is still pretty smooth and fluid, you can just spoon it in. I “piped” it by putting the filling in a ziplock bag and cutting the corner.
Make the frosting. In an electric mixer, mix the butter on medium speed until it is very fluffy. 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 confectioners' sugar, starting with a few tablespoons at a time of your sugar until the frosting looks thick enough to spread. At this point, add in the Irish Cream/heavy cream and vanilla and whip it until combined. Beat in as much or as little of the remaining confectioners' sugar until the frosting has reached your desired consistency. Since this is essentially a basic buttercream, here are my tips for a great buttercream: This is best done on a stand mixer! If your mixer has a glass or metal bowl, fill the bowl with HOT water from the tap and let sit for a few minutes to warm up the bowl, drain the water and dry the bowl and immediately add your butter while the bowl is still warm - this will help your butter get fluffy faster without having to microwave the butter first. If you’re spreading the frosting with a knife you might want it a little thinner. If you’re going to pipe or decorate with a pastry bag I say go a little thicker. I also thought about adding some orange zest at this point – I think that would go well – maybe will give it a shot next time.