For the chilli vinegar, combine ingredients in a small bowl. Set aside.
Heat 1 tablespoon of the vegetable oil in a wok or large frying pan over high heat. Add the rice noodles and spread them out and allow them to cook for a few seconds. Then stir-fry and allow them to cook undisturbed for another 30 seconds. Once the noodles are starting to char at the edges, add the sweet dark soy sauce and stir-fry for another half a minute. Transfer noodles to a serving plate.
Mix the chicken with the marinade ingredients.
In the same pan, heat the remaining 2 tablespoons of oil. Add the chicken and stir-fry for 3-4 minutes or until cooked through and starting to char. Then add the garlic and stir-fry for a few seconds. Add the Chinese broccoli and stir-fry for another 30 seconds. Add the chicken stock, fish sauce, sugar and ¼ teaspoon of white pepper. Stir to combine and simmer for about a minute. Then add the cornflour mixture. Simmer for another minute until thick and glossy. Pour the hot chicken and gravy mixture over the top of the noodles.
Serve with the chilli vinegar and chilli powder.
