Marinate the mutton the day before with 2tbsp raw papaya paste, 1tbsp garlicginger paste, 1tsp turmeric/haldi powder, 1½tsp coriander/dhania powder, 1tsp cumin/jeera powder, 2tsp spicy red chili powder and salt and leave in the refrigerator. (The marinade should be slightly salty).
To the marinated mutton add 1 cup curd, ½ the chopped mint and coriander leaves and juice of 2 lemons.
Heat 1½ cups oil in a kadai and fry 1 kg sliced onions till golden brown (don’t over fry them). When cool grind ¾ of the fried onions to a paste. Keep the rest aside for garnish.
Add the onion paste (keep some aside for the garnish) to the marinated mutton/gosht and mix well.
Boil the potatoes in pan of water for 20 minutes. Drain and keep aside.
Use the same oil in which the onions have been fried, and fry the potatoes for 1-2 minutes till they turn a golden brown. Remove from the oil and keep aside.
Wash the rice. Add water, whole garam masala and salt and bring the water to a boil. The rice needs to just fluff up and will feel raw when you touch it..
Drain off the water in a colander and keep the rice aside to cool.
Take a small bowl of the rice and mix it with the orange color.(this is an optional step)
Now mix this with the remaining white rice and mix well. Add the remaining mint and coriander leaves to the rice and mix well.
Heat the saffron and crush it into a powder and mix with ½ cup milk. (Use color if you do not have saffron-optional).
TO LAYER THE BIRYANI:
Heat 4-5 tbsp of oil in a 12” pan. (use the oil in which the onions have been fried). Spread the marinated mutton in the pan. Add whole green chilies (optional).
Spread half of the prepared rice on the mutton and spread the potatoes and whole green chilies on top.
Layer the remaining rice on top of the potatoes and garnish with fried onions.