Put the noodles in a large bowl, then pour over enough boiling water to cover. Set aside and wait for the noodles to reach an al dente texture. Meanwhile, put the basil, coriander, peanuts, chilli, lime zest and juice, sesame oil, 1 tbsp of olive oil, 2 tbsp of water and a pinch of salt in a food processor and whizz into a pesto.
Heat the remaining oil in a large non-stick pan and quickly stir-fry the prawns for 3-4 mins, then stir in the pesto. Drain and add the noodles, season with black pepper and mix well, so that the noodles are completely coated in the pesto – if it looks a little dry, add a splash of hot water. Spoon into bowls, squeeze over extra lime juice and sprinkle over more coriander, if you like.