boneless, skinless chicken breasts • veg oil • medium onion, cut into 12 wedges • peppers, red, green, orange or yellow, deseeded and cut into chunks of about 3cm/1¼in • x 225g/8oz can water chestnuts • x 425g/15oz can pineapple chunks in natural juice drained • garlic cloves, peeled and crushed • g/1oz piece fresh root ginger, peeled and finely grated • freshly ground black pepper • Sauce • Juice from 2 tins pineapples approx 300ml • cornflour •