Mix the ingredients from yogurt to salt to marinate the chicken. Add the chicken, toss well and marinate as long as possible.
In a large pan, heat the oil plus ghee. Add the onions along with the whole spices and saute till golden brown. Add the chicken along with all the marinade and give a good mix. Add the tomatoes and potatoes and cook till the chichken is almost done.
Meanwhile, boil lots of water and cook the rice for around 8 minutes or till a little undone. It should have a bite in between. Drain the rice, wash well and set aside.
Fry the onion for the dum in the ghee.
In the saucepan meant for the dum, spread a thin layer of rice. Put all the chicken masala on top and then spread the remaining rice.
Sprinkle in the saffron milk, the fried onions, green chillies, coriander leaves and the lemon juice.
Close tight and cook on dum on meduim-low heat for around 15-20 minutes. Switch off and allow to rest for 10 minutes.
For serving, give a good mix and serve hot with raita and achaar.