Heat the oil in a pan and fry off the onion until softened
Add the chicken and stir until browned
Stir the curry paste and tomato paste together to coat the chicken well and let cook to season for a couple of minutes
Stir in the chopped tomatoes and coconut milk and let simmer gently for 15 minutes then stir through the chutney / sugar and some chopped fresh coriander if you like
Serve with rice and naan bread
Kids love it, not too spicy!