Malaysian prawn and coconut laksa nods to several countries; the ingredients are slung together in a curry with vermicelli, offered with shallots, cucumber, and dill.
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.