1. Heat olive oil in a large pot over medium heat. Sear beef cubes until browned on all sides. Remove and set aside.
2. In the same pot, sauté onion and garlic until softened. Return beef to the pot and pour in beef broth.
3. Add thyme and bay leaf. Bring to a boil, reduce heat, and let simmer for 1.5–2 hours until beef is tender.
4. Add cheese tortellini and cook according to package instructions, about 5–7 minutes. Season with salt and pepper to taste.
5. Serve hot, garnished with Parmesan cheese and fresh parsley.