Dissolve the stock cube in a pan of boiling water, add the noodles, and return to a boil.
Add broccoli and boil for two minutes, then drain and rinse both with cold water.
Slice chicken into strips and prepare mushrooms, onion, pepper, garlic, and ginger.
Heat 5ml of oil in a wok and stir-fry chicken over high heat for two minutes until browned.
Remove the chicken from the pan and set aside on a plate.
Heat remaining oil in the pan and stir-fry peppers, onions, and mushrooms for a few minutes until tender.
Add garlic, ginger, and chilli flakes and fry for a few seconds until fragrant.
Combine the noodles, broccoli, chicken, and hoisin mixture in the pan and stir-fry until hot.
Drizzle with sesame oil, top with nuts, and serve immediately.