Heat oil in large skillet. Add patties and cook over medium heat until well-browned on both sides, about 4 minutes per side. Remove patties and set aside. Drain fat from skillet.
In same skillet over medium heat stir in remaining soup, mushrooms and water, blending well. Return patties to the skillet. Reduce heat to low, cover and simmer until cooked through, about 20 minutes, turning patties occasionally and spooning gravy on top.