Bailey's Irish Cream Brownies

Preheat oven to 350 degrees F (175 degrees C).

Butter the bottom of a 10 1/2x15 1/2-inch jelly roll pan.

Place fudge brownie mix into a large bowl; beat in 1 cup of Irish cream liqueur vegetable oil and eggs until the mixture forms a smooth batter.

Spread the batter into the prepared jelly roll pan.

Bake in the preheated oven until the brownies are set and a toothpick inserted into the center comes out clean about 20 minutes. Remove pan from oven and allow to cool completely.

Beat unsalted butter in a large bowl until smooth; beat in 5 tablespoons Irish cream liqueur until mixture is creamy.

Slowly beat in confectioners' sugar 1 cup at a time until frosting is desired stiffness; spread frosting on brownies to serve.