Thoroughly mix the beef, pork, salt, pepper, garlic powder, onion powder, Worcestershire sauce, bread crumbs, onion, egg and water in a bowl. Shape into 4 oval patties.
Heat the oil in a 10-inch skillet over medium-high heat. Add the patties and cook for 10 minutes, flip over and cook another 10 minutes or until well browned on both sides. Remove patties from skillet and set aside. Add sliced mushrooms to skillet and sauté over medium heat until tender, about 10 minutes. Pour off any fat.
Stir golden mushroom soup into mushroom mixture. Return patties back to skillet. Add the beef gravy and reduce the heat to low. Cover and simmer for 20 minutes or until the patties are done. Recipe Note: If mixture appears to thick, stir in a few tablespoons water or beef broth.