Mushroom mornay sauce

MMMMM----- Recipe via Meal-Master (tm) v8.04
  
       Title: Mushroom Mornay Sauce
  Categories: Sauces
       Yield: 16 Servings
  
       1    Can condensed Cream of
            -Mushroom Soup
     3/4 c  Milk
     1/4 ts Dry mustard
       1    Egg
     1/2 c  Shredded Swiss cheese (2 oz)
       1 tb Grated Parmesan cheese
  
          Desired hot cooked vegetables
   
   In 1 1/2-quart saucepan, stir soup; stir in milk and
   mustard until smooth. Over medium heat, heat through,
   stirring occasionally.
   In small cup, lightly beat egg. Stir some hot soup
   mixture into beaten egg. Stir egg mixture back into
   soup in saucepan.
   Over low heat, cook until mixture thickens, stirring
   constantly. DO NOT BOIL! Remove from heat. Stir in
   Swiss and Parmesan. Cook until cheese melts. Serve
   over vegetables. Makes about 2 cups sauce.
  
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