This recipe comes from Natalie's grandma.
Melt butter in heavy saucepan. Stir in brown sugar, light Karo syrup, and Eagle brand milk. Use a candy thermometer while cooking caramels on the stove the entire time. Hold the temperature of the candy thermometer at 212° for 10 minutes. Then cook until temperature reaches 240°. Keep stirring caramels entire cooking time. After temperature reaches 240° remove from heat and add vanilla, stirring in well. Pour caramels into a greased 15-1/4 by 10-1/4 by 3/4 inch cookie pan. Place cookie pan with caramels in refrigerator until set, about 1-2 hrs. Cut into bit-size pieces and wrap each piece in wax paper. Delicious and attractive!