Fry the onion and celery together. Layer the bread (bottom) vegetables, and cheese in an oiled casserole dish. Pour the creamed corn over the top. Then pour the egg mixture over that. Let it stand 30 minutes, then bake in a 350° oven for 1 hour, placed in a pan of hot water.
As a main dish, this supplies about 40% of a day's protein requirement. By protein complementarity, the available amount can be increased to 55% by adding 3/4 cup sunflower seeds, but some people don't like crunchies in it.