Garnishes (optional): Chopped green onions, shallots and cilantro, lime wedges, and fresh chopped red chillies or Asian-style chili sauce.
Place coconut milk, curry paste, fish sauce, brown sugar and lime juice in a wok or large skillet. Bring to a gentle simmer and cook 10 minutes. While this occurs, bring a large pot of water to boil. Boil noodles 1-2 minutes, or until just tender. Drain noodles well, and then add them, the shrimp and cilantro to the skillet. Gently stir and cook 3-4 minutes more. Divide noodles among plates or bowls. Serve garnishes in small bowls alongside for guests to top the noodles as they like.
Note: Green curry paste, coconut milk, fish sauce and rice noodles - the wider style is preferably for this dish - are available in the Asian food aisle. Noodle package sizes vary. If what you purchased is larger than 250 grams, use what you need and save the rest for another use.