Preheat oven to 350°. Spray a 4-quart baking dish with cooking spray. Set aside.
In a large Dutch oven, heat 1/4 cup vegetable oil over medium-high heat. Add onion, celery, and
bell peppers. Cook, stirring frequently, for 10 minutes. Add rice; cook for 2 minutes, stirring
constantly. Add broth and tomatoes; bring to a boil. Reduce heat to medium-low, and cook,
covered, until rice is tender, approximately 20 minutes. Remove from heat.
In a medium skillet, combine remaining 1/2 cup vegetable oil and flour; cook over medium heat,
stirring constantly, until roux is a caramel color, about 10 minutes. Transfer roux to
Dutch oven.
Add sausage, okra, hot sauce, Worcestershire sauce, Creole seasoning, and garlic powder to
Dutch oven, stirring to combine. Spoon mixture into
prepared pan.
Cover with heavy-duty foil, and bake until heated through, 30 to 45 minutes. Uncover, and
garnish with green onions and oregano, if desired.