Heat oil in a very large (7 quart or larger) Dutch oven.
Add the sausage and brown lightly on all sides. Remove.
Add the onion, celery, and bell pepper. Saute for 5 minutes.
Add the garlic and cook another minute.
Add the stock. Bring to a boil and reduce to a simmer and continue simmering for 15 minutes.
Add the chicken, reserved smoked sausage, mushrooms, green onions, parsley, salt, cayenne pepper and hot sauce.
Cover and simmer another 15 minutes.
Add the rice, reduce heat to low, cover and cook for 45 minutes or until the rice is tender, stirring every 15 minutes.