Tomato Gumbo with Sea Bass

Cover and refrigerate the bass fillets. Wash the reserved skeleton and head in cold water, then cut the skeleton into pieces and set aside.

In a large heavy saucepan over high heat, warm 4 tablespoons of the vegetable oil. Add the onion, flour and sausage and sauté until the flour turns a medium-to-dark brown and exudes a slightly nutty aroma, 6-8 minutes. Add the bell pepper, celery, garlic, 1 teaspoon salt, peppercorns, thyme, bay leaf, tomatoes and water. Stir well. Add the reserved fish skeleton and head and bring to a boil. Reduce the heat to medium and skim away any scum that rises to the surface. Simmer, uncovered, for 1 hour.

During the final 10 minutes the gumbo is cooking, prepare the sea bass. Cut the fillets into 4 equal pieces and season lightly with salt. In a large frying pan over medium heat, melt the butter with the remaining 1 tablespoon oil. Add the fish pieces and sauté until lightly browned on the undersides, 4-5 minutes. Turn over the fish and cook until the fish is opaque throughout, 4-5 minutes longer, depending upon the thickness of the fillets.

Remove the gumbo from the heat. Remove and discard the skeleton and head. Strain through a fine-mesh sieve into a small saucepan, pressing hard on the solids to extract as much liquid as possible. Add the lemon slices and parsley, then stir in the filé powder.

TO SERVE: Ladle the gumbo into warmed soup bowls, place a piece of fish in each and garnish with the parsley sprigs.