Easy sweet & sour chicken

INGREDIENTS

• 9 tbsp tomato ketchup
• 3 tbsp malt vinegar
• 4 tbsp dark muscovado sugar
• 2 garlic cloves , crushed
• 4 skinless and boneless chicken breast , cut into chunks
• 1 small onion , roughly chopped
• 2 red peppers , seeded and cut into chunks
• 227g 8 oz can pineapples pieces in juice, drained
• 100g sugar snap peas , roughly sliced
• handful salted, roasted cashew nuts, optional