1. Marinate the prawns in ½ teaspoon turmeric powder, a good pinch of salt, black pepper and half of the chilli powder and set aside until needed.
2. Wash the rice really well in several changes of water or until the water runs clear. Leave it to soak.
3. Heat the oil and ghee in a large heavy bottomed saucepan with a lid. Add the whole spices and cook for 30 seconds, or until aromatic.
4. Add the onions and ½ teaspoon of salt and cook until soft, stirring occasionally, then turn the heat up and cook until golden. Meanwhile, drain the rice and add it into the golden onions. Stir well over a high heat to dry off any excess water and coat the rice in the oil for about 2-3 minutes. Add your water to the pan, taste and season well. Add 1 teaspoon of the lemon juice and extra curry leaves, slightly torn. Bring to the boil, then cover it and turn the heat right down. Cook undisturbed for 7-8 minutes then test a grain. If it is done, take off the heat and set aside for 10 minutes.
5. Spoon the rice onto some open plates to prevent them overcooking. You can use this pot for the final assembly.
6. Heat 1 tablespoon of oil in a medium sized non-stick saucepan. Add the marinated prawns in and sauté for 1 minute. Spoon them out and set aside. Add the remaining oil and ghee and heat before adding the onions, cook really well until very soft and golden. Add the curry leaves, ginger and garlic and sauté over a gentle flame, for about a minute, until the garlic is cooked through. Add in your spices, tomatoes and seasoning and sauté for a few minutes. Add a splash of hot water and continue to cook for 8-10 minutes, until the tomatoes have collapsed, darkened and the paste releases some oil. Check the taste, it should be harmonious, if not then cook it a little longer, adding some water if you are worried about it being too dry but then cook it down to a paste before the next stage.
7. Add your prawns back in along with the herbs, 2 teaspoons of lemon juice ad a good splash of hot water and cook for 2-3 minutes, or until the prawns are cooked through. Taste it, it should be delicious, adjust the salt and chilli powder at this stage if necessary.
8. The sauce should not coat the prawns but also not be a big curry. Take it off the heat.
9. Place six cubes of the butter on the base of the rice pot. Layer over half of the rice, sprinkle over the extra ½ teaspoon of garam masala and herbs. Then spoon over all the prawn mixture and finally top it with the remaining rice and butter.
10. Cover it with a tea towel and a lid, making sure the tea towel edges are on the lid and not near the heat. When you are ready to cook, place it over a really low heat for 20-30 minutes, or until it steams when you take the lid off.
11. Leave it off the heat for 10-20 minutes before serving.
12. Sprinkle over the crispy onions and serve.
Recipe courtesy of Anjum Anand