Makes about 2 1/2 pounds
1 cup butter or margarine
1 pound brown sugar
1 cup light corn syrup
1 14oz can of sweetened condensed milk
1 teaspoon vanilla extract
Melt butter in a heavy saucepan. Add brown sugar and salt. Stir until thoroughly combined. Stir in corn syrup and mix well. Gradually add milk, stirring constantly.
Cook and stir over medium heat until candy reaches firm ball stage. 245 degrees on candy thermometer; about 12 to 15 min.
Remove from heat, stir in vanilla. Pour into a buttered 9-inch square pan. Cool and cut into squares.