Cut all fat away from meat; cube meat into large pieces and brown. Clean and cube all vegetables. Simmer meat, adding half of the cleaned carrots, half of the onions, all of the celery, and the vinegar. When meat and vegetables are cooked to tender, remove carrots, onions, and celery. Discard. Put in remaining carrots and onions and simmer again. Cook until tender and add mushrooms. Thicken stew as you would gravy. Season with salt, pepper, and garlic to taste.