Place hamburger, garlic and onion in a medium kettle on medium heat.
Break up burger and stir occasionally as hamburger browns. (If hamburger has high fat content, drain excess fat before proceeding)
Stir in bell pepper, celery, Cajun seasoning, salt, rice and beef broth.
Bring to a boil; reduce heat to low and simmer covered ~25 minutes, or until rice is cooked and liquid is absorbed.
Allow to sit for 5 to 10 minutes, then fluff with a fork.