Heat the olive oil in a large pot or Dutch oven over medium-high heat. Season the beef with salt and pepper, then add it to the pot. Cook for about 5–7 minutes, stirring occasionally, until the beef is browned.
Pour in the red cooking wine and scrape the bottom of the pot with a wooden spoon to deglaze, lifting any browned bits. Let the wine simmer for about 2–3 minutes.
Add the beef broth, carrots, celery, chopped onion, mushrooms, garlic, and bay leaf. Stir everything together and bring the soup to a gentle boil.
Reduce the heat to low, cover, and simmer for about 1 hour, stirring occasionally, until the vegetables and beef begin to soften.
Stir in the barley and continue simmering uncovered for about 30 minutes, or until the barley is tender.
Remove the bay leaf and adjust seasoning with salt and pepper if needed.