In a large enameled cast-iron casserole, whisk the flour with 1/2 cup of oil until smooth. Cook the roux over moderately low heat, whisking often, until deep brown, about 1 hour and 15 minutes. Add the onion, celery, bell peppers and garlic and cook over moderately low heat, stirring, until the onion is translucent, about 20 minutes.

Gradually add the stock to the casserole, whisking until smooth. Add the andouille, bay leaves, jerk paste, thyme and paprika and bring to a simmer. Cook over low heat for 45 minutes, stirring occasionally.

Add the okra to the casserole and simmer until tender, 15 minutes. Stir in the chicken meat and season the gumbo with salt, pepper and Tabasco. Discard the bay leaves, ladle the gumbo over rice, garnish with the scallions and serve with Tabasco.