Ingredients:

  Amount  Measure       Ingredient -- Preparation Method
--------  ------------  --------------------------------
   1      medium        Vidalia onion -- chopped
   3      cups          Swiss cheese -- shredded
   1      cup           mayonnaise -- (low-fat ok)
   1      tablespoon    Dijon mustard
     1/8  teaspoon      pepper

Preparation:

Preheat oven to 325F. Combine all ingredients and spoon into a 1-quart baking dish. Bake at 325F for 25 minutes or until lightly browned on top.