Toasty Cheese Bake

8 slices bread
soft margarine
1/2 pound extra lean ground beef
1/4 cup chopped onions
2 tablespoons chopped celery
1 tablespoon prepared mustard
1/2 teaspoon salt
1 cup shredded cheddar cheese, 4 oz.
1 egg, slightly beaten
3/4 cup 1% low-fat milk
1/2 teaspoon salt
pepper to taste
1/8 teaspoon dry mustard

Preheat oven to 350F.

Toast bread and butter both sides. Cook and stir meat, onions, celery, prepared mustard and 1/2 teaspoon salt until meat is brown and onion is tender. Alternate layers of toast, meat mixture and cheese in a greased 9x9-inch pan.

Mix remaining ingredients and pour over layers in the pan.

Bake uncovered 30-35 minutes.