Ingredients
1 teaspoon whole black peppercorns, coarsely ground
1 teaspoon whole coriander seeds, coarsely ground
2 fresh lemongrass stalks, bottom 5 inches only, chopped
6 fresh or frozen kaffir lime leaves, shredded, or 1 teaspoon finely grated lime zest
1 piece (2 inches) peeled fresh ginger, coarsely chopped
4 shallots, coarsely chopped, plus more sliced for serving
4 garlic cloves, coarsely chopped
4 small fresh Thai chiles
3 large dried mild red chiles, seeded and soaked until soft
10 ounces rice vermicelli or other thin rice noodles
1/3 cup unsalted peanuts, coarsely ground
3 tablespoons vegetable oil
2 tablespoons Asian fish sauce
2 cans (14 ounces each) coconut milk
1 3/4 cups homemade or low-sodium store-bought chicken, fish, or vegetable stock
12 prawns or jumbo shrimp, peeled and deveined, tail left intact
Juice of 1 lime
1 bunch fresh dill, coarsely chopped
Preparation
Working in batches, pound peppercorns, coriander seeds, lemongrass, and lime leaves with a mortar and pestle until beginning to break down. Add ginger, shallots, garlic, and chiles; pound until a coarse paste forms. Alternatively, pulse ingredients in a food processor.
Bring a large pot of water to a boil. Add noodles; cook according to package instructions, about 3 minutes. Drain.
Heat a wok or large pan over medium-high heat. Add peanuts; cook, tossing occasionally, until lightly toasted, 1 to 2 minutes. Add oil; heat until hot but not smoking. Add peppercorn paste; cook, stirring constantly, until fragrant and darkened, 1 to 2 minutes.
Add fish sauce, coconut milk, and stock; bring to a simmer, and cook, stirring occasionally, about 5 minutes. Add prawns; cook, stirring occasionally, until prawns are cooked through, 3 to 7 minutes. Stir in lime juice, noodles, and half of the dill. Divide among 6 serving bowls. Serve with remaining dill and sliced shallot, cucumber, chiles, and scallions.
