This is a deceptively simple dish that everyone loves. It shows just how good lentils can be. I often make it to do several meals and it never lasts as long as I think it will because I can't resist just one more mouthful...
Wash your lentils well and soak in cold water for an hour before cooking.
Put the drained lentils and the spices in a medium-sized pot and add the cold water. Bring to the boil and then simmer for an hour, adding water if it looks dry and stirring frequently.
The lentils will mush up and disintegrate into a soup. Once this happens, take off the heat and leave to one side while you start the tarka. This allows the lentils to thicken slightly.
Melt the butter in a frying pan over a low heat. Skin the tomatoes and cut them into small dice, and then fnely chop the chillies, garlic and ginger. Fry everything gently in the butter for at least 20 minutes until the tomatoes collapse.
Stir the tarka into the daal, garnish with fresh coriander and fnely sliced pieces of ginger and you have tarka daal!