As an Iranian, I've never heard of this dish and I'm certain there is no braise or stew with dates in it (at least not in persian cuisine). However the name sounds persian and your father in law is close, except date in persian is spelled "Khorma" (it has an h).
The word "Korma" in this dish name does not mean "date" and it simply means "braise" which is also a reason to not look for a braise with dates in it. Korma is an Urdu word which you can verify via link below.
http://en.wikipedia.org/wiki/Korma
Speaking of culinary anthropology, in the middle ages, Persians brought their cuisine to the Indian subcontinent, and to this day a lot of Persian and Hindi names for many dishes are similar. I would safely assume this dish is Hindu or Indian. However, if you are looking to make a stew with chicken and spices, you are welcome to visit my blog and try my Curry Stew which is a delicious Persian/Indian concoction. It does have chicken and a yummy curry sauce. Here is the link, hope you can try and enjoy it. Good luck.
http://www.tumblingpots.com/1/post/2013/12/curry-stew.html