Drain the lentils and place in a heavy-based pan with a lid. Add the ground turmeric and 1 teaspoon of the salt. Pour in enough water to cover the lentils by 7.5cm/3in. Place over a medium heat and bring to a simmer, then cover with a lid and simmer gently for 30 minutes or until the lentils are tender. You can also use canned lentils to simplify things.
While the lentils are cooking, prepare the meat. In a wide, heavy-based frying pan, heat the ghee or oil over a medium–high heat. Add the bay leaf, cassia bark and cardamom pods. Stir for a few seconds, then add the onion and fry gently until caramelised
Add the meat and fry, stirring regularly to seal on all sides. Next, add the garlic, ginger, chilli powder and remaining 3 teaspoons of salt. Stir for 1 minute to allow the spices to brown. Now pour in 250ml/9fl oz cold water, bring to a simmer and cook very gently for 1–1¼ hours, or until the meat is tender.
Remove the lid and allow any excess liquid to evaporate and the oil to seep to the edges of the pan. Add the lentil purée to the meat, stir to mix and taste for seasoning. Stir through the tomato purée and the tamarind pulp or lemon juice.
To make the tempering, heat the ghee or oil over a high heat in a small frying pan. Add the garlic, cumin seeds, dried red chillies and curry leaves. Cook for 1 minute, then pour the tempering oil, garlic and spices over the warm dal in the pan. Next, take a spoonful of the dal and place it in the frying pan to absorb any remaining oil – take care whilst doing this as the oil may splutter – then tip the spoonful of dal from the frying pan back into the main dal pan. Taste to check the seasoning and adjust as necessary
Spoon the meat and lentils into a big serving bowl and serve immediately. Serve with rice, naan or paratha