Add beef pieces and sear until browned on the outside with a rich aroma

Stir in chopped onion, carrot, and celery, cooking until slightly softened and fragrant

Add garlic and cook briefly until aromatic but not browned

Mix in tomato paste and cook for a minute to deepen its flavor

Pour in beef broth and water, scraping the bottom to release browned bits

Stir in barley, thyme, salt, and pepper until evenly combined

Bring the soup to a gentle boil, then reduce heat to a steady simmer

Cook until the barley is tender and the broth thickens slightly

Finish with a splash of red wine vinegar for brightness and balance

Taste and adjust seasoning before serving hot