In a large bowl, mix ground beef, rice, egg, onion, garlic, cumin, oregano, salt, and pepper.
Form the mixture into small meatballs, about 1 inch in diameter.
In a large pot, heat the beef broth over medium heat.
Add diced tomatoes to the pot and bring to a simmer.
Carefully drop the meatballs into the simmering broth.
Add sliced carrots and diced celery to the pot.
Allow the soup to simmer for 25-30 minutes, or until meatballs are cooked through.
Taste and adjust seasoning as needed.
Serve hot, garnished with fresh cilantro.
Enjoy your delicious albondigas soup!