Soak rice vermicelli in cold water for 30 minutes.

Pound Thai chiles and garlic to a paste with 1 tablespoon of sugar.

Add lime juice, fish sauce, boiling water, and remaining sugar to the paste.

Pound until sugar dissolves and let the dressing stand for 30 minutes.

Bring a large saucepan of water to a boil.

Fill a bowl with ice water.

Add shrimp to the boiling water and cook until white throughout and curled, 2-3 minutes.

Transfer shrimp to ice water using a slotted spoon.

Add scallops to the boiling water and cook until white and firm, 2-3 minutes.

Transfer scallops to ice water.

Drain all seafood and pat dry.

Bring a fresh saucepan of water to a boil and refill the bowl with ice water.

Drain the vermicelli and add to the boiling water.

Cook vermicelli until al dente, about 1 minute.

Drain vermicelli and transfer to ice water.

Drain vermicelli again and pat dry.

Cut vermicelli into 3-inch lengths.

In a large bowl, toss the seafood with the vermicelli, tomatoes, bean sprouts, mint, red onion, peanuts, and chile dressing.

Arrange lettuce leaves on a platter and fill with the seafood salad.

Garnish with cilantro leaves and serve.