Trim excess fat from steak. Cut steak into 1" cubes. In Dutch oven, heat oil over medium-high heat. Add steak and saute for 5 minutes. Add onions and garlic and saute for 5 minutes or until onions are tender.
Add carrots, celery, salt, rosemary, thyme, pepper, bay leaf, parsley, barley, stock and wine: stir well to mix.
Cover and bake at 350°F for 1 1/2 hours. Stir in mushrooms and bake an additional 1 hour or until meat is tender. Remove bay leaf and discard.