1 1/2 c. brown sugar, firmly packed
1 1/2 c. granulated sugar
1 1/2 c. milk
2 tbsp. butter

Combine sugars and milk, and bring to boil, stirring constantly. Then boil, without stirring, until a small amount forms a soft ball in cold water (232 degrees on candy thermometer). Add butter; cool and beat until of right consistency to spread.