Scalloped Potatoes

Scalloped Potatoes 1/4 cup onion, chopped 1/4 cup butter 1/4 cup flour 1 1/2 teaspoons salt 1/8 teaspoon pepper 2 1/2 cups milk 5 large potatoes, peeled and thinly sliced ( about 5 cups) To make sauce, cook onion in butter till tender but not brown. Stir in flour, salt and pepper. Add milk. Cook and stir till thickened and bubbly. Cook and stir 1 to 2 minutes more. Remove from heat. Place half of the sliced potatoes in a greased 2 quart casserole. Cover with half of the sauce. Repeat layers. Bake, covered, in a 350* oven 45 minutes, stirring once. Uncover, bake 30 to 45 minutes more or until potatoes are done.