1/ Marinate the lamb: Cut the lamb into bite-sized pieces and place them in a bowl. Add the yogurt, salt, turmeric powder, grated ginger, and garlic, then mix well until the lamb is evenly coated. Let it marinate for 30 minutes to 2 hours. You can also marinate it overnight for a deeper flavor. If you are using bone-in lamb, keep the bones in, as they will add extra flavor and richness to the curry as it simmers.
2/ Prepare the vegetables: Finely chop the onions. Cut the tomatoes into small pieces, about 1 cm cubes.
3/ Temper the whole spices: Heat the oil or ghee in a heavy-bottomed pot over medium heat. Add the cumin seeds, bay leaves, and cloves, and fry them gently until fragrant. Once the spices have infused the oil, you can leave them in the curry. If you prefer, you can remove the bay leaves and cloves later.
4/ Cook the onions slowly: Add the chopped onions to the pot and cook them slowly over medium heat. Add a pinch of salt while cooking to help draw out moisture from the onions. Cook for about 15 minutes, or until the onions turn a deep golden brown. This step adds natural sweetness and depth to the curry.
5/ Add the tomatoes and ground spices: Add the chopped tomatoes and cook while gently breaking them down. Add the coriander powder, turmeric powder, cinnamon powder, and chili powder if using. Cook until the moisture from the tomatoes has reduced and the mixture becomes thick and paste-like. You should see a little oil separating from the masala; this is a sign that the onions, tomatoes, and spices have cooked together well.
6/ Add the marinated lamb: Add the marinated lamb to the pot, including all the marinade. If you are using bone-in lamb, add the bones as well. Stir everything together and cook for 2–3 minutes, just until the surface of the lamb is lightly cooked.
7/ Add water and simmer: Add 280–300 ml of water and mix well. Bring to a boil, then reduce the heat. Cover the pot with the lid slightly ajar and simmer for 45–60 minutes. Stir occasionally from the bottom of the pot to prevent sticking. Continue cooking until the lamb is tender and the sauce has developed a rich flavor.
8/ Add the cashew nuts: Add the roughly crushed cashew nuts and simmer for another 10–15 minutes. If you prefer a smoother texture, crush the cashew nuts more finely before adding them.
9/ Reduce the sauce: Remove the lid and simmer for about 10 minutes, or until the curry reaches your preferred consistency. For a lighter curry, reduce it for a shorter time. For a richer, thicker curry, simmer a little longer.
10/ Finish the curry: Just before turning off the heat, add the garam masala and adjust the seasoning with salt. This final touch brings out the aroma of the spices. If you like, add 1 tsp of butter or ghee at the end for extra richness.
Mild North Indian-Style Lamb Curry
