Beat eggs in a large bowl. Add the celery, onion, bean sprouts, mushrooms, chicken, beef, pork, salt and pepper. Mix together.
Heat oil in a medium skillet or wok and brown egg mixture 1/2 cup at a time. When all of the mixture is browned, set aside.
To Make Sauce: Dissolve the bouillon in the hot water in a small saucepan; add sugar and soy sauce and blend well over medium heat. Add cold water and cornstarch and stir until thick and smooth. Serve with Egg Foo Yung.
