Marinate the chicken with yoghurt with little salt and turmeric powder for 2 hours.
Take some oil in a pan. Add shahi zeera, whole black pepper, cardamoms, cloves, cinnamon stick, bay leaves and star anise. Cook for 1 minute.
Add ginger garlic paste. Cook for another minute, till the raw smell goes away.
Add sliced Onions to the pan and fry . Saute the onions till they are slightly golden brown. Take around 2 tbsp of fried onion out and keep it separately for garnishing the biryani later.
Add the sliced tomatoes and cook for around 10 minutes till they become soft and mushy.
Add Chicken along with the yogurt marinade. Also add red chili powder, zeera powder, green chilies, mint leaves and coriander leaves.
Cover and let the Yakhni cook on medium to low flame for 10 minutes.
Now in another pan, add ghee, followed by shahi zeera, cardamom powder and bay leaf. Add 12 cups of water. Add salt and kewra water. Once the water boils, add a handful of mint leaves.
Add the rice and cook till the rice is half done. Usually it takes 7-8 minutes. Once the rice is half cooked, drain it in a colander.
Now layer the biryani with half rice in the bottom then chicken yakhni. Add rose water.
Cover with the remaining rice.
Garnish with fried onions, coriander leaves and mint leaves. Put it in the oven for dumm at 350F or 180C for 50 mins.
If you are using the gas stove, put the Biryani pan on a flat pan or Tava. Cook on high flame for 5 minutes and on low for another 30 minutes. Do not put your Biryani pan directly on the flame or the rice in the bottom will burn, messing up your Biryani.