Speedy green chicken curry

INGREDIENTS

• 1 tsp vegetable oil
• 1 red onion , cut into half-moon slices
• 4 tbsp Thai green curry paste
• 2 x 400g cans light coconut milk
• 2 tbsp fish sauce
• zest and juice 2 limes
• 1 tbsp brined green peppercorns , drained and rinsed
• 200g green beans , trimmed and halved
• 4 skinless chicken breasts , cut into long strips
• handful basil leaves
• cooked basmati rice , to serve