time to make 1 1/2 hours 15 min prep
1/2 cup onions, chopped fine
4 tablespoons butter
4 tablespoons all-purpose flour
1/2 teaspoon salt
1/4 teaspoon pepper
2 1/2 cups milk
2 cups cheddar cheese, grated
6 medium potatoes, peeled and thinly sliced, 6c
1. For sauce; Cook onion in butter until tender. Stir in four, salt and petter. Add milk, all at once. Cook and stir until thickened and bubbly. Stir 1 1/2 cups cheese into sauce until melted. Remove from heat. Place half the potatoes in a greased 1 quart casserole dish. Cover with half the sauce. Repeat layers.
2. Bake, covered, in a 350 degree oven for 35 minutes. Uncover bake 30 minutes more or until potatoes are tender. Sprinkle rest of chesse over top. Let stand 5 minutes.