Mint Brownies

1 box Brownie Mix
3 c. pwd. Sugar
¼ c. butter
3 TBL. Milk
1 tsp. mint extract
6 oz. semi-sweet chocolate chips
4 TBL. Butter

Follow instructions on box to make brownies. Allow to cool. Mix mint frosting by combining pwd. Sugar, butter, milk and extract. Spread over cooled brownies. Slowly melt chocolate chips with butter. Pour over mint frosting. Cut into squares and serve