I used coconut oil, but you can use ghee or refined oil also. The gravy tends to thicken as the curry rests, so adjust the consistency of the curry accordingly. It pairs well with ghee rice/pulao/roti/appam etc.; You can also add cashew paste to make it creamier. Soak 1-2 tbsp of chopped cashews in 2 tbsp hot water for 10-15 mins. Grind it to a smooth paste. Mix the cashew paste with thick coconut milk and add it to the curry.