- 1 lb jumbo (8 to 12 per lb) shrimp
- 2 teaspoons sea salt dissolved in 1 cup water
- 4 to 8 (1- to 2-inch) fresh red Thai chiles, minced
- 2 fresh serrano or jalapeño chiles (preferably red), minced
- 1 tablespoon minced garlic
- 3 tablespoons Asian fish sauce (preferably Thai naam pla)
- 3 to 4 tablespoons fresh lime juice
- 2 to 3 teaspoons sugar
- 2 stalks fresh lemongrass
- 2 small shallots, halved lengthwise and thinly sliced crosswise (1/4 cup)
- 2 scallions (white parts and half of greens), thinly sliced
- 1/2 cup fresh mint leaves, torn into pieces
- Accompaniments: green-leaf lettuce, sliced tomato, and fresh cilantro or mint sprigs
- Prepare grill for cooking.
- Soak shrimp (still in shells) in salt water 5 minutes, then rinse well in a colander.
- Pound all chiles with garlic to a coarse paste with a mortar and pestle and stir in fish sauce and lime juice and sugar to taste. Transfer to a large bowl.
- Snip shells of shrimp with scissors down center of back, from wide end to second-to-last tail section. Butterfly shrimp in their shells, making a deep incision along length of back where shells are cut, and devein.
- Discard tough outer leaves of lemongrass and trim root ends. Thinly slice lower 6 inches of stalks.
- Grill shrimp on their sides on an oiled rack set 5 to 6 inches over glowing coals until shells are pink and slightly charred and shrimp are just cooked through, 3 to 4 minutes on each side. (Alternatively, grill shrimp in a hot well-seasoned ridged grill pan over moderate heat.)
- Toss shrimp (with shells still on) with chile mixture and stir in sliced lemongrass, shallots, scallions, and mint.
- Serve on a bed of lettuce and tomato with cilantro or mint.