1. Heat olive oil in a large pot over medium heat. Sear beef cubes until browned on all sides. Remove and set aside.
2. Add onion, garlic, and carrots to the pot. Sauté until softened. Stir in flour and cook for 1 minute.
3. Add tomato paste, beef broth, and Italian seasoning. Return beef to the pot, bring to a boil, then reduce heat and simmer for 1 1/2 to 2 hours, until the beef is tender.
4. Stir in tortellini and cook for 5-7 minutes, until tender. Adjust salt and pepper to taste.
5. Ladle into bowls, top with shredded cheese, and serve hot.