Clean, de-vein and wash prawns thoroughly under running water. Drain well. Apply a little salt and turmeric powder. Set aside. Reserve one tablespoon scraped coconut and grind the remaining with one and a half cups of warm water. Squeeze and extract coconut milk. Heat half a tablespoon of oil in a pan and sauté the prawns on medium heat for two to three minutes.
Remove from heat and set aside. Heat remaining oil in the same pan, add bay leaves, green cardamoms, cloves and cinnamon. Stir-fry briefly. Add grated onions and sauté for two to three minutes or until the onions turn translucent. Blend red chilli powder in a little water and add to onions.
Stir-fry on medium heat for two to three minutes or until oil separates. Add ginger paste and continue to cook for about two minutes sprinkling little water from time to time to prevent burning. Add the sautéed prawns and coconut milk. Adjust salt and simmer for two minutes. Mix in pure ghee and the reserved scraped coconut and serve hot.