Korma, the curry of the Nawabs, is a mild, rich, thick curry. The base is rich and is mildly flavoured by expensive spices.
Originating in the kitchens of Lucknow, the Korma soon spread across the country. In Hyderabad, the mild Mogul korma bumped into the strong spices of the south. It gradually accommodated them, evolving into a spicier version, coming to be called the Kuruma.
North Indian Kormas are built from dairy products ( milk / cream / yogurt). South Indian Kurumas are built from coconut paste / coconut milk. Like any curry using milk products, a korma will split (solids separate) on prolonged cooking or high heat. So it should be cooked gently, over a slow fire, with frequent stirring. This would ensure a creamy curry.
Using boiled vegetables greatly shortens the cooking time and reduces the risk of the korma curdling.
Korma is aristocrat’s curry. The only question you have to ask yourself while cooking a korma is “ Will a Nawab eat this ?” So the spirit of a korma calls for expensive spices and goodies. If you want to use saffron / vanilla bean as flavouring, go right ahead – the Nawabs would be proud of you! Kormas using less expensive goodies like spinach / boiled pulses are not very common. However, a variety of Korma called the Navratan korma using a mixture of nine vegetables is very popular. In fact, if the Kerala Aviyal is flavoured with expensive spices, it could pass off as a Navratan Korma !
Though traditionally eaten with naan, rotis or rice, a korma goes equally well as a sauce with pasta or noodles. Being very mild, it serves an excellent introduction to Indian cuisine. See Param’s Chana Kurma, Divya’s Vegetable kurma, Cook simple’s Cashew Korma, Heidi’s Navratan Korma.