1 c. butter
1 lb. brown sugar
pinch of salt
1 c. light Karo
1 can sweetened condensed milk
1 t. vanilla

Melt butter in heavy saucepan; add brown sugar and salt. Mix well; add Karo and milk and mix well. Blend and bring to boil. Stir constantly to 240 degrees, remove from heat.
Add vanilla. Pour onto buttered 13 x 9 pan. Cool. Cut into pieces and wrap in waxed paper.