1. Dice chicken in 2cm cubes and roughly chop onion.
2. Heat oil or ghee in a saucepan then fry the onions until softened, then add chicken fillet and seal.
3. Add the curry paste, garlic, tomatoes, chicken stock and chilli flakes to the pan and simmer for 15 minutes,or until the sauce thickens.
4. Add coriander to taste.
5. Serve with basmati rice or naan bread.