Cook the rice: Prepare the white rice according to package directions. Fluff with a fork and cover to keep warm.
Make the roux: In a large pot or Dutch oven, heat the vegetable oil over medium heat. Add the flour and stir continuously to create a roux. Cook until it turns deep brown, stirring frequently to prevent burning.
Sauté the vegetables: Add the onion, green bell pepper, celery, and garlic to the roux. Cook for 5–7 minutes, until softened.
Add the proteins: Stir in the diced chicken thighs and sliced andouille sausage. Cook until browned on all sides.
Build the gumbo: Add the diced tomato, chicken broth, bay leaf, thyme, oregano, paprika, cayenne pepper, Worcestershire sauce, salt, and black pepper. Stir well.
Simmer: Bring to a boil, then reduce heat and simmer uncovered for 30 minutes, stirring occasionally. Cook chicken to an internal temperature of 165°F (74°C).
Finish and serve: Discard the bay leaf. Serve the gumbo hot with a scoop of rice. Garnish with sliced scallions.
Enjoy: Pair your bowl of gumbo with a glass of cold coconut water.