Guinness Brownies with Maple Buttercream Frosting

Renee's Kitchen Adventures

Rich, fudgy brownies made with the goodness of Guinness draught!


  • 1 cup of Guinness beer, at room temperature
  • 1 cup all purpose flour
  • 3/4 cup unsweetened cocoa powder
  • 1/2 tsp. kosher salt
  • 8 oz. bittersweet chocolate (60% to 70% cacao), chopped
  • 3/4 cup white chocolate chips
  • 6 TBS unsalted butter, cut into chunks
  • 4 eggs, room temperature
  • 1 cup granulated sugar
  • 1/2 cup semi-sweet chocolate chips
  • 1/4 cup unsalted butter, room temperature
  • 1/4 tsp. kosher salt
  • 2 to 2 1/2 cups powdered sugar
  • 1 tsp. maple extract
  • 2 - 3 TBS milk to thin frosting


  1. Pour out beer into a glass measure and allow to sit until the foam has disappeared. Do not count the foam in the measurement. You should have a full 8 oz. of beer once it's settled.
  2. Preheat oven to 350 degrees F. Spray a 13" x 9" glass baking dish with cooking spray. Set aside.
  3. In a small saucepan over low heat, melt the butter, bittersweet chocolate and the white chocolate chips, taking care not to heat too much. (can also be done in a double boiler). Allow to cool slightly.
  4. In large bowl, whisk together flour, cocoa powder, and salt. Set aside.
  5. In medium bowl, combine the eggs and sugar. Slowly add the melted chocolate mixture, a little at a time to temper the eggs, and then mix until well combined.
  6. Add the chocolate/egg mixture to the flour mixture and stir well. Batter will be thick. Whisk in reserved beer. Batter will turn thin. Add semisweet chocolate chips to batter.
  7. Pour batter into prepared pan. Bake in oven for 25 - 30 minutes, or until a toothpick comes out clean.
  8. Cool brownies on wire rack and prepare the frosting.
  9. To prepare the frosting: In a large bowl, beat the butter and salt with an electric mixer until fluffy. Add in powdered sugar, by cupfuls and mix well after each addition. Add in maple flavoring and milk. Whip until creamy.
  10. Once brownies are completely cool, frost the tops with prepared maple buttercream frosting.
  11. Cover with plastic wrap and place in refrigerator for several hours or overnight. Cut into 24 bars.

Yield: 24 servings

Prep Time: 00 hrs. 10 mins.

Cook time: 00 hrs. 30 mins.

Total time: 40 mins.