1/2 c. (1 stick) butter
1/2 c. firmly packed light brown sugar
1/4 c. evaporated milk
2 1/4 c. confectioners' sugar
1 tsp. vanilla

In quart saucepan heat together butter and brown sugar over low heat, stir constantly until sugar melts. Blend in milk; cool. Gradually beat in sugar until you obtain spreading consistency, then add vanilla. 13 x 9 inch pan.