Marinate chicken and potatoes with yogurt, chilli powder, ginger-garlic paste, turmeric powder and Biryani masala. and some whole spices. Set aside for atleast a1 to 2 hours.
Wash and soak the basmati rice for atleast 15 - 20 minutes
In a thick bottom vessel in which you will assemble your biryani, heat 1 cup oil and fry the sliced onions till golden brown.
Once the onions are fried remove and spread it on a plate to cool. once cool crush it with your fingers.
Now add the marinated chicken to the remaining oil and also the fried onions and mint leaves.
In another big vessel bring water to a rolling boil. Add a few whole garam masala like bay leaves, cloves, pepper, star anise and salt. Also add a few drops of lemon juice.
Put in the soaked rice and cook till 70% done and drain it into a colander.
Spread this rice on to the marinated chicken evenly. Pour in the saffron-infused milk. Put 1 tbsp ghee all over the rice and top it with some fried onions.
Cover the vessel with a tight fitting lid. Place some weight on it so as not to let the steam escape. Place it on dum, ie high flame for 5 minutes.
Place a griddle or tawa under the vessel and reduce the flame to medium low. Keep it on dum for another 15 minutes.
Now reduce the flame to the lowest and let it cook on dum for another 15 minutes. You know your biryani is done when you get a nice aroma from the rice. Switch off the flame and keep the vessel covered for 15 minutes before you serve the biryani.
Total time for cooking the Chicken Dum Briyani is 35 minutes.
Serve with riata or salad.