Slow Cooker Tomato Tortellini Soup with Ground Beef

1. In a skillet, cook the ground beef, onion, and garlic until the beef is browned. Drain any excess fat.
2. Transfer the beef mixture to a slow cooker. Add the beef broth, crushed tomatoes, basil, oregano, red pepper flakes (if using), salt, and black pepper. Stir to combine.
3. Cover and cook on low for 6-8 hours or on high for 3-4 hours.
4. About 30 minutes before serving, add the tortellini and spinach. Cook until the tortellini is tender.
5. Serve hot, topped with grated Parmesan cheese. Enjoy this hearty, comforting soup!