Scalloped Potatoes

3 tablespoons butter
2 tablespoons flour
1 1/2 tsp. salt
1/8 tsp. pepper
3 cups milk
6 medium potatoes, pared & thinly sliced (6 cups)
2 tablespoons chopped onion
ham - about 2 or 3 handfuls - chopped

Make white sauce of first 5 ingredients *. Place half the potatoes in greased 2 qt. casserole; cover with half the onion, ham & half the sauce. Repeat layers. Cover & bake at 350 about 1 hour. Uncover & bake 30 minutes longer.

White sauce:
Melt butter in saucepan over low heat. Blend in flour, salt & pepper. Add milk all at once. Cook quickly, stirring constantly, till mixture thickens & bubbles. Remove sauce from heat when it bubbles. Add cheeses or other flavorings at this point, stirring till smooth.