Brown andouille sausage in a Dutch oven ove medium heat, stirring until it crumbles and is no longer pink. Remove sausage, reserving dripping in pan. Set sausage aside.
Cut chicken breasts and thighs into 1-inch pieces, and brown in hot drippings over medium heat. Remove chicken, reserving drippings.
Measure drippings, adding enough olive oil to measure 1/2 cup. Heat mixture in Dutch oven over medium-high heat until hot. Whisk in flour , and cook, whisking constantly, 10 to 12 minutes or until roux is caramel colored.
Add chopped onion and next 3 ingredients; cook, stirring often, untilvegetables are tender. Gradually stir in 4 cups water and broth; bring to a boil. Add chicken, Creole seasoning, and next 3 ingredients; reduce heat, and simmer, stirring occasionally, 30 minutes.
Add sausage and green onions, and cook 30 minutes. Remove and discard bay leaves; serve over rice. Serve with filé powder, and garnish, if desired.