Make a batter with flour, cornflour and water. You need about two-thirds flour and one-third cornflour. Mix with water to the consistency of double cream.
Stir in the chicken strips until they are evenly coated.
Heat oil in a wok or deep-fryer. The oil should be deep enough to completely cover the pieces of chicken when they are put in it.
Once the oil is hot (test by dropping in some of the batter off a teaspoon - it should rise quickly to the surface sizzling gently), add the pieces of chicken a few at a time and fry until golden-brown. You will need to do this in several batches. As each batch is cooked, put to one side to drain.
Take a clean wok and heat a couple of tablespoons of oil in it.
When hot, add the onions, pepper and chilli and stir fried for a couple of minutes until the onion starts to turn translucent.
Add the fried chicken strips and stir thoroughly for a minute or two.
Stir in a generous quantity of sea salt and ground black pepper.