Add the leeks and stir-fry for 1 minute further, until they begin to wilt. Add the stock, a generous pinch of salt, sugar, wine and toss well to combine. Add a little of the cornstarch slurry ...
Add the spring onions, chilli and ginger and cook for just 30 seconds. Add the marinated sirloin strips and stir-fry for 2–3 minutes, until well sealed and lightly coloured. Add the peppers ...