Sweet & sour chicken

Name: Sweet & sour chicken
Prep time: 20 min
Cook time: 45 min
Total time: 1 h 5 min
Cuisine: Chinese
Ingredients: sunflower or vegetable oil , for frying; 100ml soda water , chilled; 140g self-raising flour; 25g cornflour; 4 skinless, boneless chicken breasts , cut into chunks; spring onions , finely shredded, to serve; 1 red pepper , deseeded and chopped into chunks; 3 red chillies , 1 cut into chunks, 2 halved and deseeded; 425g can pineapple chunks, drained and juice reserved; 4 star anise; 50g tamarind paste; 100g caster sugar; 100ml rice wine vinegar or Chinese vinegar