Butter bread on one side, then cube. Grease a large shallow baking dish. Put in 1/2 of the bread cubes, them 1/2 the cheeses, 1/2 ham, 1/2 onion and repeat all. Combine the rest of the ingredients and pour over layers. Refrigerate 8-24 hours then bake at 325 degrees for one hour. Serve hot as an entree. Can be baked and reheated. May also be frozen after baking. Serves 8-10