Soak the rice for 30 minutes, rinse well and set aside. Peel the potatoes and cut in halves, place it in some water to prevent discolouration.
Heat the oil in a large pot. Add the whole spices and once the seeds starts to splutter add the onion.
Allow the onion to brown and add the curry leaf and thyme.
Add the lamb and allow it to brown for a couple of minutes. Add the ginger garlic paste and cook for a couple of minutes.
Add the ground spices. Cook for 2 minutes and add the tomato paste and blended tomatoes. Do not cover the pot. Cook for another 10 minutes. Cover the pot and cook for another 1/2 hour.
Preheat the oven to 160 degrees celsius.
After 30 minutes add the potatoes and rice. Add mint and coriander. Add the hot water, start with 3 cups and add more later in the cooking process, if required. Add the blobs of butter on top
Cook in the oven for 1 hour, remove the pot from the oven and check if the rice and lamb is tender. If not add more water and cook for a further 30 minutes. Check again and cook for a further 30 minutes, if required.
Garnish with coriander and serve with raita