The BEST way to impart real Guinness flavor into chocolate cupcakes is to reduce it down on the stove first. This packs in flavor without altering the cupcake’s texture. Read the recipe in full before beginning.
Duration:
- Prep Time: 35 minutes
- Cook Time: 20 minutes
- Total Time: 3 hours, 35 minutes (includes cooling)
- Yield: 16 cupcakes
Ingredients
- one 12-ounce (355ml) bottle Guinness beer
- 1 cup (125g) all-purpose flour (spooned & leveled)
- 1/2 cup (41g) unsweetened natural cocoa powder
- 1 and 1/2 teaspoons espresso powder
- 3/4 teaspoon baking soda
- 1/4 teaspoon salt
- 1/2 cup + 1 Tablespoon (135ml) vegetable or canola oil
- 1 cup (200g) packed light or dark brown sugar
- 2 large eggs, at room temperature*
- 3/4 cup (180g) full-fat sour cream, at room temperature*
- 2 teaspoons pure vanilla extract
Mocha Guinness Buttercream
- 2 Tablespoons reduced Guinness from step 1
- 2 teaspoons espresso powder
- 1 and 1/4 cups (282g) unsalted butter, softened to room temperature
- 4 and 1/2 cups (550g) confectioners’ sugar
- 1 Tablespoon (5g) unsweetened natural cocoa powder
- 1 Tablespoon (15ml) milk
- 1 teaspoon pure vanilla extract
- pinch of salt, to taste
Instructions
- In a small saucepan, bring the Guinness to a boil over medium-high heat. Once boiling, reduce to medium heat and allow to simmer until reduced down to 2/3 cup, about 20 minutes. Set 1/2 cup aside to cool for 10–15 minutes before using in the cupcake batter. While it’s warm, mix the rest of the reduced Guinness (about 2–2.5 Tablespoons) with the 2 teaspoons of espresso powder used in the frosting. Set this mixture aside for step 5. You can do this step 1 day ahead of time if needed. Refrigerate overnight. Bring reduced beer to room temperature before using in both the cupcake batter and frosting.
- Preheat the oven to 350°F (177°C). Line a 12-cup muffin pan with cupcake liners. Line a second pan with 4 liners—this recipe makes about 16 cupcakes. Set aside.
- Whisk the flour, cocoa powder, espresso powder, baking soda, and salt together in a large bowl until thoroughly combined. Set aside. In a medium bowl, whisk the oil, brown sugar, eggs, sour cream, and vanilla together until completely smooth. Pour the wet ingredients into the dry ingredients, add the 1/2 cup (120ml) reduced Guinness, then whisk until *just* combined. Do not over-mix. The batter will be on the thinner side.
- Pour or spoon the batter into the liners. Fill each 2/3 full to avoid spilling over the sides or sinking. Bake for 19–22 minutes, or until a toothpick inserted in the center comes out clean. Don’t over-bake, which will dry out the cupcakes. Begin checking for doneness at 19 minutes. For around 36 mini cupcakes, bake for about 11–13 minutes, same oven temperature. Allow the cupcakes to cool completely before frosting.
- Make the frosting: Have the Guinness/espresso powder mixture from step 1 handy. In a large bowl using a handheld or stand mixer fitted with a whisk attachment, beat the butter on high speed until completely smooth and creamy, about 2–3 minutes. Add the confectioners’ sugar, cocoa powder, milk, reduced Guinness/espresso powder mixture, milk, and vanilla extract. Beat on low for 30 seconds then increase to high speed and beat until combined and creamy. Taste. Add a pinch of salt if desired. (I always add 1/8 teaspoon.) If you want the frosting a little thicker, add 1/4 cup (30g) of confectioners’ sugar.
- Frost cooled cupcakes. I piped a basic tall swirl using Ateco 849 piping tip.
- Leftover cupcakes keep well covered tightly in the refrigerator for 3 days. I recommend a cupcake carrier for storing and transporting decorated cupcakes.
Notes
- Make Ahead & Freezing Instructions: Cupcakes can be made ahead 1 day in advance, covered, and stored at room temperature. Freeze frosted or unfrosted cupcakes for up to 2–3 months. Thaw overnight in the refrigerator.
- Special Tools (affiliate links): 12-cup Muffin Pan | Cupcake Liners | Glass Mixing Bowls | Whisk | Electric Mixer (Handheld or Stand) | Piping Bag (Reusable or Disposable) | Ateco 849 Piping Tip | Cupcake Carrier (for storage)
- Espresso Powder: I highly recommend this addition to deepen the chocolate and stout flavors, though you can leave it out in the cupcakes and frosting if necessary. Espresso powder is like instant espresso, found in the coffee aisle. You can also use instant coffee granules. (Not ground coffee.) Read through the recipe before beginning because you will actually use the espresso powder needed for the frosting in step 1.
- Sour Cream: Sour cream is strongly recommended for the best taste and texture. A full-fat plain yogurt would work instead, though the cupcakes may not be as light.
- Milk in frosting: You can use any milk, dairy or nondairy. You could also use heavy cream or half-and-half, too.
- Why is everything at room temperature? All refrigerated items should be at room temperature so the batter mixes together easily and evenly. See my post on why room temperature ingredients are important for more information.
- Be sure to check out my 10 tips for baking the BEST cupcakes before you begin!
