Sauté beef- Melt butter over medium heat in a large (4 quart or larger; this makes a big batch and a small pot is not recommended) pot. Add beef cubes, and season with salt and pepper. Sauté for 5 minutes, or until browned all over.
Add worcestershire- Drizzle worcestershire sauce all over the beef; toss to coat and simmer for one minute.
Add vegetables- Next, add the onion, garlic, carrots and celery to the pot. Cook, stirring occasionally, for 7-10 minutes, until softened.
Add other ingredients- Add the bay leaf, salt, pepper, thyme leaves, beef stock and barley to the pot. Cover, bring to a boil, reduce the heat, and simmer for one hour, or until barley is cooked through.
Finishing touches- Remove the bay leaf, and taste. Adjust salt as needed. Serve with a crusty loaf of bread, and enjoy!