For the broth:
- 3 tablespoons extra-virgin olive oil
- 1 medium yellow onion, finely diced
- 1 small fennel bulb, trimmed, cored, and finely diced
- 6 garlic cloves, minced
- ¼ teaspoon crushed red pepper flakes
- 2 tablespoons tomato paste
- 1 cup dry white wine
- 1 (28-ounce) can whole peeled tomatoes, crushed by hand with their juices
- 3 cups low-sodium seafood stock
- 1 bay leaf
- ½ teaspoon dried oregano
- ¼ teaspoon freshly ground black pepper
- Kosher salt, to taste
For the seafood:
- 1 pound littleneck clams, scrubbed, weighed with shells
- 1 pound mussels, scrubbed and debearded, weighed with shells
- 1 pound skinless cod, cut into 1½-inch pieces
- 1 pound large raw shrimp, peeled and deveined
- ½ pound cleaned raw calamari, tubes cut into ½-inch rings and tentacles left whole
For finishing and serving:
- ¼ cup chopped fresh flat-leaf parsley
- 1 tablespoon fresh lemon juice, plus more to taste
- Lemon wedges
- Crusty bread, optional