For the gravy, pour Vanaspati ghee (vegetable oil) in a pan. To this, add all whole garam masalas and cook for a few minutes till the mixture turns light brown. This way, the oil is infused with the flavours of these masalas.
Remove the whole garam masalas with a slotted spoon. In the same oil, add cumin seeds and let them crackle. To this, add finely chopped onions and cook till the mixture turns brown. When done, the oil will separate and the onions will come together.
In a blender, combine these onions with curd to make a smooth paste.
Now add some more ghee to the pan and add the paste. Let it cook for 2-3 minutes. To this, add turmeric, slit green chilies, cumin powder and coriander powder. Next add the cashew, chironji and charmagaz pastes.
Let the gravy simmer for a few minutes until the curd is cooked. Keep stirring to keep the gravy from sticking to the bottom of the pan and getting burnt. If the gravy becomes too thick, add some water and continue to cook till it is done. It will take about 3-4 gentle simmers (cook for approximately 15 minutes).
For the koftas, mash boiled potatoes, grate the paneer and ginger, and chop green chilies and coriander leaves finely. Now mix all of these together along with salt and garam masala.
Prepare the filling by mixing all the filling ingredients together. Mash and mix well.
Take some of the kofta mixture in your hand and roll it into a small ball. Make a well in the centre of the ball with your thumb and put the filling in it. Pinch the kofta ball together, gently rounding it again between your palms till the filling inside is completely covered.
Put the kofta balls aside and let them rest for about 30 minutes. Dust the balls in corn flour and fry in hot oil over low flame to ensure the kofta is well cooked on the inside and outside.
Before adding koftas to the gravy, if required, thin down the gravy with water or cream. Add the koftas to this gravy and cook again for about 5 minutes.
To garnish, mix some saffron strands into hot milk and pour over the koftas.
Serve hot with rice or naan.
Tip#1: Vanaspati ghee helps the gravy congeal when stored in the deep freezer.
Tip#2: For best results, the kofta mixture should be rested for some time before making the koftas.
Tip#3: During the preparation of the gravy, keep the cashew and charmagaz paste separate. If mixed together and kept aside, the paste will turn grey.