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Guinness Brownies with Frosting

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Rich, fudgy brownies with a deep chocolate flavor enhanced by reduced Guinness stout, topped with a silky frosting that retains a hint of beer flavor.
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Prep Time 25 minutes
Cook Time 32 minutes
Total Time 2 hours 27 minutes
Servings: 16 squares
Course: Dessert
Cuisine: Irish
Calories: 370
Ingredients Method Nutrition Notes

Ingredients
  

Brownie Ingredients
  • 11.2–12 ounces Guinness Draught Stout beer, reduced Reduces down to concentrate flavor and remove some alcohol; yields about 2/3 cup for the batter and a few tablespoons for the frosting.
  • 3/4 cup unsalted butter Adds richness and helps create a fudgy crumb.
  • 8 ounces semi-sweet chocolate, coarsely chopped Melts into the butter to form the chocolate backbone of the brownies.
  • 1 1/4 cups granulated sugar Sweetens the batter and contributes to a shiny brownie top.
  • 3 large eggs, at room temperature Provide structure, moisture, and glossy sheen when beaten into the batter.
  • 1 teaspoon pure vanilla extract Enhances the chocolate and malt flavors.
  • 1 cup all-purpose flour Gives structure without making the brownies cakey.
  • 1/2 teaspoon salt Balances sweetness and intensifies chocolate flavor.
  • 1/2 teaspoon espresso powder (optional) Boosts chocolate depth and complements the stout; optional but recommended for a richer profile.
Frosting Ingredients
  • 1/2 cup unsalted butter, softened The base for a creamy, spreadable frosting.
  • 2 cups confectioners’ sugar Sweetens and stabilizes the frosting to a smooth consistency.
  • 2–3 tablespoons reduced Guinness Adds signature stout flavor; adjust between 2 and 3 tablespoons to reach desired consistency and taste.
  • 1 teaspoon espresso powder A small boost of coffee flavor that enhances the chocolate and stout notes.
  • 1/2 teaspoon pure vanilla extract Rounds and lifts the frosting flavor.
  • 1/4 teaspoon salt Balances sweetness and brightens the overall taste.

Method
 

Preparation
  1. Reduce the Guinness. Pour the 11.2 to 12-ounce bottle into a small saucepan and simmer over medium-high heat until reduced to about 2/3 cup. This concentrates the flavor and evaporates some alcohol. Remove from heat and let cool while you prepare other ingredients.
  2. Preheat and prepare the pan. Preheat your oven to 350°F (175°C). Grease a 9-inch square baking pan with butter or nonstick spray, or line it with parchment for easier removal.
  3. Melt butter and chocolate. Place 3/4 cup unsalted butter and 8 ounces coarsely chopped semi-sweet chocolate in a microwave-safe bowl. Microwave in 20 to 30 second bursts, stirring between bursts, until completely smooth to avoid overheating the chocolate.
  4. Combine sugar and reduced Guinness. Whisk 1 and 1/4 cups granulated sugar into the melted chocolate mixture, then whisk in the cooled reduced Guinness until evenly incorporated.
  5. Add eggs and vanilla. Add the 3 large room-temperature eggs one at a time or all together, whisking until the mixture is glossy. Stir in 1 teaspoon pure vanilla extract.
  6. Fold in dry ingredients. Gently mix in 1 cup all-purpose flour, 1/2 teaspoon salt, and 1/2 teaspoon espresso powder if using, until just combined. Avoid overmixing to keep the brownies fudgy.
  7. Bake the brownies. Pour the batter into the prepared 9-inch square pan and smooth the top. Bake in the preheated oven for 32 minutes. Check doneness by inserting a toothpick into the center; it should come out with a few moist crumbs but not wet batter.
  8. Cool completely. Remove the pan from the oven and let the brownies cool completely in the pan. Cooling fully is important so the frosting does not melt.
  9. Make the frosting. In a mixing bowl, beat 1/2 cup softened unsalted butter until creamy. Gradually add 2 cups confectioners’ sugar while mixing on low. Add 2 to 3 tablespoons of the reduced Guinness, 1 teaspoon espresso powder, 1/2 teaspoon pure vanilla extract, and 1/4 teaspoon salt, and beat until smooth and spreadable.
  10. Frost, set, and store. Spread the frosting evenly over the cooled brownies. Let the frosting set at room temperature, then cut into squares. Store the brownies at room temperature in an airtight container.

Nutrition

Serving: 1gCalories: 370kcalCarbohydrates: 56gProtein: 3gFat: 16gSaturated Fat: 10gSodium: 250mgFiber: 1gSugar: 38g

Notes

When melting chocolate, short microwave bursts and stirring prevent scorching. Use room-temperature eggs to help the batter emulsify and become glossy. To test doneness, look for a shiny top and moist crumbs on a toothpick rather than a completely clean toothpick. Store frosted brownies at room temperature in an airtight container for up to 3 days. If your kitchen is warm, store in the refrigerator and bring to room temperature before serving for the best texture. Freeze unfrosted brownies tightly wrapped for up to 3 months. Thaw overnight in the refrigerator and frost before serving.

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