Heat the vegetable oil in a large pot over medium-high heat. Brown the beef on all sides, then remove to a plate.
Add a bit more oil if the pot is dry. Add the onion, garlic, celery, and carrots to the pot. Saute for 5-6 minutes until softened.
Add the tomato paste and cook for 1 minute.
Add the beef broth, beef (along with any juices), Worcestershire sauce, dried thyme, and bay leaf. Bring to a simmer, then lower the heat, cover, and cook for 45 minutes.
Stir in the barley, cover, and simmer for another 45-60 minutes, or until the beef and barley are tender.
Remove the bay leaf. Taste and season with salt and pepper.
Nutrition information is calculated using an ingredient database and should be considered an estimate.