1/2 c. tomato soup or tomato sauce
1/2 c. cider vinegar
1/2 c. sugar
1/2 c. butter or margarine
1/2 c. French mustard
1 egg yolk

Place all ingredients in a double boiler and mix well. Cook over boiling water until thick. When still somewhat runny, cool and put in container. Refrigerate. It will thicken when cool. Serve as dip for vegetables.