Source: Sander's - Detroit, Michigan
1 (13 ounce) can Pet milk
1 pound Kraft's caramels
1/2 pound butter
12 ounces Nestle's Milk Chocolate
Combine all ingredients in the top of double boiler over simmering water; stir until smooth. Continue to cook for 30 minutes, stirring to prevent scorching.
Put hot sauce through blender or beat at high speed with electric mixer for a few minutes. Pour into refrigerator containers with lids, refrigerating sauce between usage for up to 2 weeks.