Heat a heavy based pan and add a pat of butter and the onions. Saute the onion till transparent. Add the tomato and the remaining butter. Continue to cook on medium to high, until the tomato starts to break down and the sauce reduces slightly.
Add all of the remaining spices and saute for another couple of minutes. Add the coconut cream/heavy cream and turn the temperature down. Stir in the sweetener if you are using it.
Add the diced chicken and simmer in the sauce until the chicken is tender and cooked through, usually for about 20-25 minutes. Note that if you use chicken with bones intact, this dish will take up to 45 minutes or longer to cook through.
To Serve
Drizzle the additional cream/coconut cream on top of the curry and sprinkle with fresh chopped coriander to serve.
Notes
Tastes amazing the next day when the flavors have developed.Recipe suitable for freezing.To make the flavor more subtle simply add some additional coconut cream or cream.