2/3 cup sweetened condensed milk
1/4 cup vinegar or lemon juice
1/4 cup salad oil or melted butter
1 egg yolk
1/2 teaspoon salt
few grains cayenne pepper
1 teaspoon dry mustard

1. Place ingredients in mixing bowl.
2. Beat with rotary beater until mixture thickens.
3. If thicker consistency is desired, place in
refrigerator and chill before serving.

Makes 1 1/4 cups

Source: Eagle Brand Sweetened Condensed Milk ad,
Otawa Citizen newspaper, July 9, 1942