Combine beef, onion, and garlic in a large pot over medium heat. Cook until browned, 5 to 10 minutes. Drain and discard excess grease.
Pour beef broth into the pot. Add tomatoes with their juice, brown rice, salt, pepper, and paprika. Bring to a boil, cover, and simmer for 1 hour. Add green bell peppers; cook, uncovered, until soft, about 30 minutes.