Sweet and Tangy Pineapple Chicken

Name: Sweet and Tangy Pineapple Chicken
Cook time: 35 min
Total time: 35 min
Cuisine: Malaysian
Ingredients: 1 kg boneless chicken thighs/breasts, cleaned and cut into bite-sized pieces; 1 kg boneless chicken thighs/breasts, cleaned and cut into bite-sized pieces; 2 Tbsp sesame oil; 1 tsp ground white pepper; 2 Tbsp vegetable oil; 2 star anise (optional); 10 cm young ginger, peeled and thinly sliced; 4 tomatoes, chopped or a can (400 g) of chopped tomatoes; 1 Tbsp dried chilli paste/powder; 1 Tbsp dried chilli paste/powder; ½ cup mirin/vinegar; ½ cup mirin/vinegar; 1 small ripe pineapple/canned pineapple, cut into bite-sized pieces; 1 small ripe pineapple/canned pineapple, cut into bite-sized pieces; 1 onion, peeled and cut into wedges; 1 bell pepper, deseeded and cut into wedges; Salt to taste; 5 stalks spring onions, sliced into 3 cm lengths