Insalata di Pesce

Fill a large bowl with ice water; set aside. Bring 10 cups water to a boil in a large saucepan over medium-high. Reduce heat to medium, and stir in 3 tablespoons salt. Working in batches, add scallops, shrimp, and fish to boiling water; cook to desired degree of doneness (45 seconds to 1 minute and 30 seconds for scallops, depending on size; 1 to 2 minutes for shrimp; 2 to 3 minutes for swordfish). Using a slotted spoon, transfer cooked seafood to prepared ice water; let stand 30 seconds to 1 minute. Transfer to a colander; drain well, and transfer to a medium bowl.

Add celery, shallot, parsley, oil, lemon juice, black pepper, crushed red pepper (if using), and remaining 1/4 teaspoon salt to seafood mixture; gently stir just until combined. Let stand at room temperature 5 minutes. Add additional salt, oil, lemon juice, or black pepper to taste. Serve seafood salad with lettuce or radicchio and lemon wedges.