Cook the noodles following pack instructions, then drain and rinse under cold running water to prevent them sticking. Heat the oil in a large frying pan or wok over a medium-high heat and cook the onion, carrot and broccoli for 4-5 mins until starting to brown. Add the garlic and chilli, and cook for 1-2 mins more.

Mix the soy sauces, chilli sauce, lime zest and juice in small bowl, then add to the pan along with the noodles. Toss with tongs to coat everything, then serve topped with chilli oil and cashews, if you like.