Heat olive oil in a large pot over medium heat.
Add the onion, carrots, and celery, then sauté for 4–5 minutes until softened.
Stir in the minced garlic and cook for 30 seconds.
Pour in the beef broth and bring to a gentle boil.
Add the cooked beef pieces and simmer for 15–20 minutes to blend the flavors.
Season with salt, black pepper, and thyme to taste.
Serve hot, garnished with fresh parsley if desired.