Potato and Egg Casserole

1. 1. Prepare cooked potatoes by peeling and dicing.
2. Slice hard-boiled eggs; chop onions.
3. 2. Prepare thin white sauce.
4. In a heavy skillet, melt 6 tablespoons margarine; blend in 3 tablespoons flour with a wire whisk.
5. Slowly pour in 3 cups milk, stirring constantly.
6. Cook for 2 minutes.
7. 3. In a 2-quart casserole, layer potatoes, eggs, onions and salt and pepper to taste.
8. Make 3 layers.
9. Pour hot white sauce over the top and sprinkle with bread crumbs which have been mixed with melted margarine.
10. Bakei in 350-degree oven for 1 hour.