Cheeseburger Pie

This is a very old recipe given to me by a high school friend.  Her mother-in-law got the recipe from her mother.  It is a little different than most of the versions out there, but it is fabulous!!  Use a homemade pie crust if possible.  

1 lb. ground beef

1 tsp. salt

1/2 tsp. oregano

1/4 tsp. pepper

1/2 cup dry bread crumbs

1 Cup tomato sauce

1/4 cup onion, chopped

1/4 Cup green pepper diced

Brown meat; drain.  Stir in other ingredients.  Pour into pastry-lined pie pan and pour cheese topping over. --TOPPING:-- 1 egg 1/4 Cup. milk 1/2 tsp. prepared mustard 1/2 tsp. Worcestershire sauce 2 Cups. cheese, shredded  Beat egg and milk.  Stir in seasonings and cheese.  Pour over meat.  Bake at 425 degrees for 30 minutes.