- 1 navel orange
- 1/2 cup plus 2 tablespoons fresh orange juice
- 1/4 cup fresh lime juice
- 1/2 cup diced (1/4 inch) seeded watermelon
- 1/2 teaspoon finely grated peeled fresh ginger
- 1 1/2 tablespoons finely diced red onion
- 2 to 3 teaspoons finely chopped fresh jalapeño chile
- 1/2 teaspoon salt
- 1/4 lb sea scallops, tough muscle removed from side of each if necessary and scallops cut into 1/2-inch pieces
- 1/4 lb large shrimp in shell (21 to 25 per lb), peeled, deveined, and cut into 1/2-inch pieces
- 1/4 lb cooked lobster meat, cut into 1/2-inch pieces
- 1 1/2 tablespoons chopped fresh mint
- 4 heads Bibb or 2 heads Boston lettuce (1 1/4 lb)
Cut peel and white pith from orange with a sharp paring knife, then cut segments free from membranes. Chop enough segments to measure 1/4 cup. Stir together chopped orange, orange juice, lime juice, watermelon, ginger, onion, jalapeño (to taste), and salt in a large bowl.
Bring a 1-quart saucepan 3/4 full of salted water to a boil, then add scallops. Reduce heat to a bare simmer and poach scallops until just cooked through, about 1 minute. Transfer with a slotted spoon to a bowl of ice and cold water to stop cooking. Return water in saucepan to a boil and poach shrimp in same manner. Drain shrimp in a colander and transfer to bowl of ice and cold water to stop cooking. Drain scallops and shrimp well and pat dry.
Add scallops, shrimp, lobster, and mint to watermelon mixture and toss to combine, then season with salt. Chill ceviche, covered, at least 1 hour. Trim and separate lettuce leaves. Serve ceviche with lettuce leaves on the side (use a slotted spoon to transfer ceviche to lettuce). Ceviche can be chilled up to 3 hours.