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.