Heat 1 tbsp oil in a large Dutch oven over medium-high heat. Add sliced andouille sausage and sauté until browned. Remove sausage and set aside.

Add 1 cup oil to the Dutch oven and whisk in 1 cup flour. Cook, stirring constantly, to make a dark roux—the color of chocolate—about up to 1 hour. Do not rush; reduce heat as needed to prevent burning.

Add diced onions, bell pepper and celery to the roux and season lightly with salt. Cook over medium-high, stirring and scraping, until softened, about 10 minutes. Lower heat if ingredients threaten to scorch.

Stir in minced garlic, cayenne and a generous grind of black pepper; cook, stirring, for 2 more minutes.

Slowly stir in chicken stock, then add bay leaves and thyme. Season lightly with salt. Bring to a gentle simmer and cook uncovered, stirring occasionally, for 1 hour.

Add okra (if using), browned sausage, shrimp and shredded chicken. Gently simmer uncovered for another hour, skimming fat from the surface as it accumulates.

Remove from heat. Stir in filé powder if using to thicken (use sparingly), season to taste with salt, and discard thyme sprigs and bay leaves.

Serve hot over warm rice and sprinkle sliced green onions on each bowl. Pass hot sauce and extra filé powder at the table for guests to add as desired.