Chicken Tikka Masala is probably the most popular dish in British Indian restaurants, even though it's not strictly an Indian recipe. While tikka (marinaded and grilled chicken or lamb) exists in India, the idea of putting the grilled meat into a curry sauce is, apparently, a British one. Wherever it came from, it's certainly delicious!
Marinade the chicken
Trim the chicken of any fat and sinew, and cut into bite-sized chunks. In a mortar and pestle or spice mill, make a paste of the ginger, garlic and cumin seeds. Squeeze the juice from the lemons and the yogurt and all other marinade ingredients. Stir into a smooth paste. Add the chicken and stir until all chunks are evenly coated. Cover the bowl with plastic film and place in the fridge for at least 2 hours, but preferably overnight.
Make the sauce / masala
If you don't have ghee you can use clarified butter, which is made by melting the butter and then straining it through a double layer of muslin cloth so the butter solids are left behind and you have a clear golden liquid. Crush the cinnamon, cloves and cardomom to a powder, and make a paste of the ginger and garlic. FInely chop the onions, heat the ghee in a large frying pan on medium heat and gently fry the onions until soft and slightly browned. Add the cinnamon, cloves and cardomom powder and cook for a minute or so, then add the other spices. After another minute, add the chopped tomatoes and the tomato puree. Stir everything well and simmer for 15 minutes.
Grill the meat
Thread the chunks of meat onto wooden or metal skewers, leaving a small gap between each one. Turn your grill on as hot as it will go, and line a roasting tin or baking sheet with foil. If possible, you want to arrange things so that the meat is not in contact with the tin. I have a roasting tin which is a bit narrower than the length of my skewers, so I simply rest the skewers across the edges. This allows the meat to cook evenly, and juices to collect in the tin.
Place the meat under the grill - as close to the heat as you can because you do want to get some charring - and cook for 10 minutes, turning once.
Finish the masala
While the meat is cooking, whizz the masala base in a blender until it's smooth. Add any remaining marinade mixture, and heat gently. When the meat is cooked, remove the chunks from the skewers and stir into the sauce. Add any cooking juices too.
Serve with rice or naan, and garnish with chopped coriander.