You may use ghee instead of oil for doing the chicken masala.
Kaima rice - which is a small variety of rice used for biriyanis in Northern Kerala - is recommended for this biriyani, however my family, including myself, are not very fond of this rice, so used basmati rice.
I fried the onions, cashews and raisins for the garnishing and used the same ghee for doing the rice.
You can serve with an egg as well. I boiled the eggs and forgot it at the time of serving as well as clicking the pics! ;)