1 can condensed sweetened milk (I use Eagle brand)
2 cups sugar
1/2 lb. butter
1 1/2 cups white corn syrup (I use Karo white)
2 teaspoon vanilla extract
Mix the milk, sugar, corn syrup, and butter in a heavy 3-quart saucepan. Cook to hard ball (260 degrees on your candy thermometer, or use the water test), stirring constantly. Remove from heat, and stir in vanilla extract.
Pour into buttered pan(s) 3/8" or less deep. Cool completely, then remove from the pans. Cut into squares of desired size and wrap individually in waxed paper, plastic or aluminum wrap.
This makes a large batch, enough to share. If anyone in your family has dental issues, you may want to cook a little less, as these will be chewy like an all-day sucker)