Sweet and sour chicken

Ingredients

• 1 x 425g can pineapple chunks in juice
• 2 teaspoons cornflour
• 1 tablespoon reduced-salt soy sauce
• 2 tablespoons rice wine vinegar
• 1 tablespoon tomato purée
• 1 teaspoon five spice
• ½ teaspoon dried chilli flakes
• 1 tablespoon vegetable oil
• 1 medium onion, cut into wedges
• 1 green pepper, cut into strips
• 1 red pepper, cut into strips
• 4–6 chicken thighs, skinless and boneless, diced
• 2 cloves garlic, crushed
• 2.5cm root ginger, peeled and finely sliced
• Freshly ground black pepper