1Preheat oven to 350 degrees F (175 degrees C). In the microwave or in a metal bowl over a pan of simmering water, melt butter and chocolate, stirring frequently until smooth. Remove from heat and set aside to cool.
2In a large bowl, beat eggs and sugar until light and pale, about 5 minutes. Fold in the chocolate mixture, coffee liqueur, Irish cream liqueur and vodka. Combine the flour and baking powder; stir into the chocolate mixture then fold in walnuts. Spread the batter evenly into a 9x13 inch pan.
3Bake for 25 minutes in the preheated oven, or until brownies begin to pull away from the sides of the pan. Cool before cutting into squares. Frost with a glaze of coffee flavored liqueur and confectioners' sugar or melted chocolate if desired.