10 cups leftover ham, 5 cups boiled diced potatoes, 1 large onion chopped, 4 Tbsp. butter, 1/2 cup flour, 2 cups grated swiss cheese, 1/2 bread crumbs.
Cube leftover ham and boiled potatoes and mix together in a large bowl. Melt butter and saute onions until tender. Gradually sprinkle in flour and stir in milk to make a smooth sauce. Add cheese and stir until melted. Pour over ham and potatoes and mix well. Put half in each of two large casserole dishes. Sprinkle 1/4 cup of breadcrumbs over each. Bake one in 350 oven for thirty minutes. Freeze the other to serve another day.