In a large pot or Dutch oven, brown the chuck roast in olive oil. Season with salt and pepper.
Add carrots, onion, and celery to the pot and sauté until softened.
Add mushrooms and garlic and cook until fragrant.
Pour in beef broth, add tomato paste, Worcestershire sauce, rosemary, and thyme. Bring to a boil, then reduce heat and simmer for 45 minutes.
Add pearl barley and continue to simmer for another 30 minutes, or until barley is tender.
Stir in ¼ cup chopped parsley. Season with salt and pepper to taste.
Serve hot, garnished with remaining parsley.