Step 1

Preheat oven as directed (325 F for Ghirardelli Dark Chocolate Brownie Mix) brownie mix box.

Step 2

Line an 8 x 8 or 9 x 9 pan, sprayed with nonstick spray and lined with parchment paper with edges of paper hanging over edges of pan.

Step 3

Place Guinness, melted butter and egg in medium bowl. Stir until fully mixed. Add brownie mix and stir until well blended. Spread in prepared pan.

Step 4

Bake for 40 – 45 minutes until brownies are set in middle and edges have begun to pull away from sides of pan. Cool completely in pan before frosting.

Step 5

Cream butter in the bowl of a stand mixer fitted with the paddle attachment until smooth and fluffy.

Step 6

Gradually beat in 2 cups confectioners' sugar until fully incorporated. Add salt and 2 tablespoons Irish Cream. Beat an additional 2 minutes. Taste; if not sweet enough add up to 1 more cup of sifted confectioners’ sugar, 1/2 cup at a time.

Step 7

Add milk or Guinness a tablespoon at a time, beating until reaching desired consistency.

Step 8

Frost brownies immediately or store buttercream in an airtight container at room temperature for up to three days. After frosting, chill briefly to allow frosting to set for easier cutting. When ready to cut, lift brownies from pan using parchment paper edges. Wipe knife after each cut for cleaner cuts. Cut into 16 squares or 32 triangles for more servings.