Heat half the oil in a wok or large frying pan, add the cashews and fry until just golden. Drain from the pan with a slotted spoon on to a plate lined with kitchen paper.
Add the red and yellow pepper slices and stir-fry for three minutes. Add the mange tout and spring onions and stir-fry for three minutes. Remove from the pan and set aside.
Add the remaining oil to the pan and stir-fry the turkey for three minutes. Mix together the hoi sin, soy and chilli sauces and pour into the pan.
Add the noodles and return the vegetables to the pan. Toss everything together over the heat for 2-3 minutes or until everything is hot.
Sprinkle over the sesame seeds, add the cashews and serve.