1/2 C. vinegar
    1 1/2 C. water
    2 tsp. butter
    2 eggs
    1/2 C. sugar
    2 T. cornstarch
    1/2 tsp. mustard (no special kind specified, but probably ordinary
    yellow or a light Dijon could be used)
    1/4 tsp. salt
    Dash of pepper
    Mix together dry ingredients and add to the beaten eggs.  Combine with
    vinegar, water, and butter which have been heated.  Cook and stir
    until thickened.