Wash prawns thoroughly under running water.

Slice two onions and chop one. Grind ginger and garlic to a paste.

Heat two tablespoons of ghee in pan. Add green cardamoms, cloves and half the crushed black peppercorns. When they change colour, add sliced onions and tomatoes. Sauté for three to four minutes.

Add one cup of water, cashewnuts and bring to a boil. Take off the heat, cool and puree in a blender.

Heat the remaining ghee in a pan, add mustard seeds and whole red chillies. When the seeds splutter add curry leaves and chopped onions and sauté till light brown. Add salt, remaining crushed black peppercorns, red chilli powder and sauté.

Add ginger-garlic paste and mix. Add prawns and sauté for two to three minutes.

Add the pureed gravy and check the seasoning. Add salt and simmer for two minutes.

Before serving add saffron dissolved in a tablespoon of warm water.

Serve hot with Pilau or Plain Rice.