Bring a small saucepan of lightly salted water to a boil. Blanch broccoli for 2 minutes. Drain and cool under cold running water.
In a cup, mix water, rice wine, soy sauce and corn flour, and set aside.
Heat a wok or large frying pan over medium heat. Add oils and, when smoking, add ginger and garlic. Cook for a few seconds, stirring constantly, then add chicken and stir-fry for 6-8 minutes, or until chicken is cooked. Remove from wok and set aside.
Add onion and capsicum to wok and stir-fry for 5 minutes, or until vegetables begin to soften. Add broccoli and toss to combine. Stir cornflour mixture, then pour into wok and stir over high heat until sauce has thickened. Return chicken to wok and toss to combine and heat through.