In a large saucepan or Dutch oven, heat vegetable oil; add beef cubes. Cook, stirring, until beef is browned on all sides. Add onion and garlic. Continue cooking, stirring frequently, until onions are tender. Add flour, stirring until beef is well coated. Add mushrooms with juice and the celery. In a small bowl, combine sour cream and tomato sauce; stir to blend well.
Pour over meat and sprinkle with salt and pepper; gently stir until well blended. Remove from heat. Turn mixture into a greased 2-quart casserole dish. Cover dish and bake at 325° for 1 1/4 to 1 1/2 hours until meat is tender. Sprinkle with chopped green onions and parsley, if desired.
Beef recipe serves 4.