Chocolate Wafer Squares

Arrange 9 wafers in a layer in an 8-inch square pan and brush with 1 tablespoon milk. Spread about 1/3 of the whipped topping over wafers. Repeat layers, ending with topping. Cover the pan with plastic wrap or aluminum foil. Freeze or chill at least 6 hours. Garnish with chocolate curls, if desired. Cut into squares.