Wash the barley. Soak it in warm water while you prepare the rest of the soup. It will be needed later.
Using a kitchen towel pat dry beef chunks really well. Season with salt and pepper.
Heat olive oil in a dutch oven. Add half of the beef chunks. Sear it on high heat for 2-3 minutes. Turn the pieces and brown for 2-3 minutes more. Using a slotted spoon remove browned beef chunks from the pot.
Add the rest of the beef chunks and brown. Keep aside.
To the same dutch oven, add chopped onion and garlic and saute for 30 seconds.
Add chopped celery, carrot, bay leaf, and thyme. Saute for 2 minutes.
Add tomato paste and saute for 2 minutes.
Stir in beef stock. Season with Soy sauce and Worcestershire sauce. Check the seasoning and add more salt if required. Add in the beef chunks. Bring it to a slow boil, then reduce heat, cover and let it cook on a simmer for 1 hour.
Add the soaked barley grains. Add it to the dutch oven. Also, stir in the mushrooms. Cover and cook again on low heat for another 45 minutes - 1 hour.
Add parsley and serve.