Thinly slice onions. Mix them with salt and oil. Microwave at high for 15 min or until crispy and slightly brown. Mix in between so that it does not get burnt.
Soak 1 cup Basmati rice for 30 min before cooking. Boil water with bay leaf, cinnamon, cardamom, cloves, shahi jeera, lemon juice and oil.
When it boils, add rice and salt. mix well and let it cook in medium flame until almost done. You can check in between if its done by trying to mash the rice
Strain it well and spread it in a plate to let it cool down.
Take a cooker, Put in Mutton, turmeric powder, chilli powder, ginger-garlic-green chilli paste, Garam masala. Finely chop coriander leaves and mint leaves and add it to the mutton.
Put in curd, salt & very little water. Mix well and pressure cook for 4-5 whistles.
Open the cooker. Mix again and layer on top with 3/4th of rice. Spread it out evenly. layer again with a handful chopped coriander and chopped mint leaves. Top it again with baked onions and saffron milk (saffron soaked in warm milk).
cover it with a damp cloth and place a lid on it. Place a very heavy vessel/container/mortar pestle on top of it to make it air tight.
Leave it for 20-30 min in simmer.Take it out and drop ghee generously and fluff the rice very gently.