1. Peel and Slice potatoes, add sliced onion, salt and pepper to taste
2. Add one cup of water and bring to a boil.  Simmer until tender.  About 15 minutes.
3. Drain any water that is left

White Sauce

1. In a pan mix margarine and Flour.  Add salt and pepper to taste
2. Add 2 cups milk to the mixture
3. Stir until thinkened.
4. Add grated cheese

In a greased casserole dish layer potatoes and ham; repeat.  Pour white sauce over everything.  Bake at 350 for 20 minutes or until bubbly.