Boiled Dressing

Scant 1/2 cup sugar, scant 1/2 cup vinegar, 1 cup sweet or sour cream, 2 level teaspoonfuls mustard, 1 teaspoonful salt, 1 teaspoonful flour, dash cayenne, 3 eggs. Mix dry ingredients, add eggs, well beaten; add vinegar and cream and cook in double boiler until thick. When ready to use add 1 cup whipped cream.