1/2 cup extra-virgin olive oil, plus more for drizzling
1 fennel bulb, cored and finely chopped
2 celery ribs, finely chopped
1 white onion, finely chopped
1 tablespoon dried oregano (preferably sicilian)
pinch of crushed red pepper
1 1/2 pounds cleaned squid—bodies cut into 1/2-inch rings, tentacles halved
2 cups dry white wine
ounce one 28- can tomato puree
2 lemons—zest of one peeled in strips with a vegetables peeler, zest of the other finely grated for gremolata
salt and freshly ground black pepper
2 cups water
1 cup bottled clam broth
12 ounces mussels, scrubbed
12 ounces littleneck clams, scrubbed
12 ounces shelled and deveined large shrimp
12 ounces skinless striped bass fillet, cut into 2-by-1-inch pieces
2 tablespoons finely chopped flat-leaf parsley for gremolata
See article on storing live shellfish
In a very large, enameled cast-iron casserole or Dutch oven, heat the 1/2 cup of olive oil. Add the fennel, celery, onion, oregano and crushed red pepper and cook over moderate heat, stirring frequently, until the vegetables are softened, about 15 minutes. Add the squid and cook over moderately low heat for 15 minutes, stirring occasionally.
Stir in the wine and bring to a boil over moderately high heat. Cook until evaporated, about 20 minutes. Stir in the tomato puree and strips of lemon zest. Season with salt and pepper and cook over very low heat, stirring occasionally, until very thick, about 40 minutes.
If entertaining, recipe can be made in advance up to this point
Add the water and clam broth and bring to a boil. Remove and discard the lemon zest. Season the broth with salt and pepper. Add the mussels, clams and shrimp, cover and cook until most of the shells have opened, about 5 minutes. Add the striped bass and cook until opaque, about 2 minutes longer.
In a small bowl make the gremolata by combining the parsley with the grated lemon zest. Spoon the stew into deep bowls and sprinkle with the gremolata. Drizzle with olive oil and serve.
