- 3/4 cup vegetable oil
- 3/4 cup bleached all-purpose flour
- 2 cups chopped yellow onions
- 1 cup chopped green bell peppers
- 1 cup chopped celery
- 1 tablespoon salt
- 1 teaspoon cayenne
- 5 bay leaves
- 8 cups water
- 1 pound medium shrimp, peeled and deveined
- 1 pound lump crabmeat, picked over for shells and cartilage
- 2 dozen oysters, shucked, with their liquor
- 2 tablespoons chopped green onions or scallions (green part only)
- 2 tablespoons chopped fresh parsley leaves
- Combine the oil and flour in a large cast-iron or enameled cast-iron Dutch oven over medium heat. Stirring slowly and constantly, make a dark brown roux, the color of chocolate, 20 to 25 minutes. Add the onions, bell peppers, celery, salt, cayenne, and bay leaves. Cook, stirring occasionally, until very soft, about 10 minutes. Add the water and stir to blend with the roux. Reduce the heat to medium-low and simmer for 1 1/2 hours.
- Add the shrimp and crabmeat and cook for 15 minutes. Add the oysters, green onions, and parsley and cook until the edges of the oysters curl, 2 to 3 minutes. Remove the bay leaves.
- Serve immediately over steamed long-grain rice in soup bowls.