1 can (4 ounces) mushroom stems and pieces, drained
In a small bowl, combine the egg, bread crumbs, garlic powder and pepper. Crumble beef over mixture; mix well. Shape into two patties; dredge in 2 tablespoons flour. In a small skillet, brown patties on both sides in oil; drain. Set patties aside.
Add the remaining flour to the skillet; whisk in water until smooth. Stir in the ketchup, Worcestershire sauce and bouillon. Add the onion and mushrooms. Bring to a boil. Return patties to the pan. Reduce heat; cover and simmer for 15-20 minutes or until beef is no longer pink. Serve gravy over patties.