Preheat the oven to gas 7, 220ºC, fan 200ºC. Break up the noodles, put on a roasting tray and add 2 teaspoons of sesame oil. Roast in the oven until golden, then set aside.
In a bowl, mix the soy and chilli sauce. Add the chicken, turn to coat, then leave to marinate for 10 minutes.
Shake the excess sauce off the chicken (and reserve for later). Tip the sesame seeds onto a plate then roll the chicken pieces in them until evenly coated.
Heat a wok until hot, add 2 tablespoons of the vegetable oil and fry the chicken pieces for 2 minutes or until golden brown and cooked through (you may need to do this in batches). When all the chicken is cooked, set aside and discard any sesame seeds that have gathered in the bottom of the wok.
Put the wok back on the heat, add the rest of the vegetable and sesame oil, then add the peppers, onion, broccoli, the marinade and a splash of water. Cover with a lid and steam for 3-4 minutes.
To serve, divide the vegetables and chicken between 4 plates, then top with the crunchy noodles.