Marinate the Chicken: Marinate your chicken in the yoghurt, turmeric, cumin, chilli powder and 1/2 of the garlic and ginger.
Prepare the Rice: Wash your rice under cold water and leave it to soak for 20 minutes.
Cook the Rice: Bring a large pot of salted water to a boil and add the rice. Cook for 6-7 minutes or until it's about 2/3 cooked, then drain the water.
Sauté Onions and Spices: In a large pot, heat the ghee and flavour with the cinnamon stick, green cardamom and coriander seeds. After a few minutes, add the onions and a tbsp of salt and sauté for 15-20 minutes, stirring often.
Set Aside Onions: Remove 1/4 of the cooked onions and set aside for the final assembly.
Add Garlic, Ginger, and Chicken: Add the remaining garlic and ginger to the pot and sauté for 2-3 minutes. Add the marinated chicken, followed by the diced tomatoes, green chillies and garam masala.
Cook the Chicken: Stir well and cook for 15-20 minutes or until the tomatoes are completely soft.
Assemble the Biryani: Start the assembly of the biryani by pouring the remaining ghee into the bottom of a large pot, followed by a layer of rice, then a layer of chicken and a sprinkling of the mint and coriander. Repeat this until all the rice and chicken is in the pot, ensuring your last layer is rice topped with the reserved sautéed onions.
Optional Saffron Milk: Optionally, you can warm 3 tbsp of milk with a pinch of saffron and pour over the final assembled biryani.
Cook the Biryani: Seal the pot by using a tea towel under the lid and cook for 25 minutes on low.
Serve: Serve with more chopped mint, coriander and some crispy shallots (optional).