Make brownies as directed on the box in 9x13" pan. Cool completely. For Filling, combine powdered sugar, butter, water, mint extract and green food coloring, if desired. Beat until creamy. Spread evenly over cooled brownies. Refrigerate until set. Or Topping, melt mint chocolate chips and butter in microwave. Spread over brownies. Chill before cutting. Store in refrigerator. |