For the Thai red curry paste, blend all of the Thai red curry paste ingredients, including the soaking water, in a food processor to a smooth paste. Keep any spare paste in a sealed sterilised jar in the fridge for up to 1 week.
For the prawn curry, heat the oil in a wok over a very high heat. Add 50g/1Â¾oz of the curry paste and stir-fry for 1-2 minutes, or until just starting to darken in colour.
Add the prawns, palm sugar, tamarind paste, water chestnuts, white pepper and coconut milk. Bring the mixture to the boil, then reduce the heat until the mixture is simmering and simmer for 10 minutes, or until thickened. Keep warm; season with the lime juice and garnish with some chopped coriander just before serving.
For the noodles, heat the oil in a wok over a very high heat. Add the chilli sauce, spring onions and red chilli and stir-fry for 1-2 minutes.
Add the cooked noodles, peanuts, soy sauce, sesame oil and coriander and and stir-fry until heated through. Season, to taste, with lime juice.
To serve, divide the noodles among four serving plates. Spoon over the prawn curry.