I have this radical idea that we should just stop eating fish out of the oceans. Bluefin tuna have become the modern equivalent of the American bison: we've fished them almost to extinction. Europeans have so decimated the fish stocks off West Africa that the locals are abandoning their homeland for lack of a catch. The once-abundant coho salmon no longer return to spawn in their former numbers on our own west coast. And the list goes on.
I follow the recommendations of the Monterey Bay Aquarium's "Seafood Watch" program, which is one of several of its kind that list which seafoods they think are sustainable and which to avoid. These days, I wistfully pass the seafood counter at the local Whole Foods, admiring the monkfish, the red snapper, the Chilean seabass--all off limits to me now.
That doesn't mean you can't eat seafood at all. Look lower down the food chain, especially to shellfish, which grow and reproduce much more quickly--and in greater profusion--than large predator fish. A classic Creole gumbo is a perfect treatment. It has just the kind of big flavors I like, and you can add almost anything to it. For this particular gumbo, I used shrimp, scallops, catfish and garlic sausage.
Gumbo starts with roux, which may be familiar to you as the basis of a Bechamel sauce. But the roux for gumbo is cooked longer. For a seafood gumbo, some say the darker the roux the better, until it is almost black. I've explained previously why a long-cooked roux doesn't thicken much. The molecules in the flour are re-arranged, so the roux is more for flavor and appearance.
For six persons, coat the bottom of a heavy pot or Dutch oven with canola oil and over high heat brown 1/2-pound Kielbasa sausage, cut into slices on an angle. Remove the sausage and lightly brown 1/2-pound sea scallops, which may need to be cut in half or into quarters if they are very large. Remove the scallops, lower the heat to moderately-low and add 1/2 cup canola oil. Stir in 1/2 cup all-purpose flour. Cook, stirring frequently, until the roux is dark brown. Do not let it burn. This could take a half-hour or more.
To the cooked roux add 1 small onion, peeled and diced small, 1 green bell pepper, seeded and diced small, 2 stalks celery, cleaned and diced small, and 3 garlic cloves, finely chopped. Cook until the onions begin to soften, about 10 minutes. Add a handful chopped parsley, 1/2 teaspoon dried thyme, 1 bay leaf, 1/2 teaspoons salt and a generous pinch black pepper to the pot, as well as the browned sausage. Pour in 4 cups stocks. This can be made with shells from your shrimp or from fish racks (skeletons) purchased from the fish monger, or use a store-bought seafood stock. I used a home-made chicken stock that was rich with flavor. Bring to a boil, then reduce heat and cook for about 20 minutes, or until the gumbo is aromatic and flavorful.
Just before serving, add 1/2-pound deveined jumbo shrimp, the scallops and 1/2-pound catfish fillet, cut into pieces, and cook just until the seafood is cooked through. Adjust seasonings, ladle gumbo over rice, such as a brown Basmati rice, and serve hot, with a flourish, perhaps garnished with more chopped parsley.
Note: The Monterey Bay Aquarium's "Seafood Watch" program advises to avoid imported shrimp and select wild-caught or farmed shrimp from the U.S. or Canada, with wild-caught shrimp from Oregon and British Columbia listed as the "best" choice. Avoid wild-caught sea scallops from the U.S. Mid-Atlantic and any kind of imitation scallop. Choose either wild-caught sea scallops from the Northeast or farmed bay scallops. Farmed U.S. channel catfish are the best choice, but other kinds of imported farmed catfish can be substituted.