Cut one half of the ginger into slices and finely chop the other half.
Marinate the chicken in sliced ginger, sliced garlic, rice wine, salt, sugar and ground white pepper and mix well. Chill for 1-2 hours.
Heat 2 tablespoons oil in a wok over medium heat until hot. Stir fry the chicken until the wok is dry. Add the tangerine peel, chopped garlic and chopped ginger. Continue to cook for another 2 minutes.
Add the Szechuan peppercorns, chilli flakes and any additional salt (if required) and fry for 5 minutes. Serve.