Drain the rice under cold running water and soak it for half an hour.

Heat a pan with 4 tablespoons of ghee in it over moderate flame. Fry the sliced onion till golden brown and remove with a slotted spoon. Drain fried slices of onion on absorbent paper.

In the same pan, saute half of the black cumin seeds till they begin to sizzle. Add cloves,cinnamon, half the nutmeg, peppercorns and saute them till they get fragrant.

Add ginger and garlic paste and saute for one minute. Now add salt, pepper, yogurt and vegetables and saute them over a low heat till the vegetables are almost tender.

In the meanwhile, in a separate large pan, bring 8 cups water to a boil with 2 teaspoons of salt.

Tie the remaining cloves, cinnamon stick, cumin seeds, black cardamoms and green cardamoms in a piece of muslin cloth to make a small bundle (potli) and add to the water with bay leaves.

Cook on low heat for 15-20 minutes to allow the spices to infuse the water with their flavor.

Drain the rice, add to the pan and cook till half done. Remove from the heat and reserve the strained water.

Stir the remaining ghee into the rice and set aside.To assemble the biryani, spread half the fried onions at the base of a deep heavy-bottomed heatproof casserole.

Spread half the rice over the onions. Then spread a layer of the vegetables and the chopped mint over the rice. For garnishing, sprinkle rose water over the rice. Serve hot!