Drain lentils and place in a large saucepan or Dutch oven. Add salt and 6 1/4 cups of water. Bring to a boil, cover and reduce heat to a slow simmer. Simmer until
the lentils are cooked and two-thirds of the liquid has evaporated: This takes approximately 3 hours. Do NOT disturb the lentils until they softened.
3) Mash the lentils slightly against the sides of the pan with a spoon. Then add ginger, garlic, tomatoes, chilies and oil. Stir and cook for another 45 minutes. Adjust seasoning if needed, add cilantro/coriander leaves and stir to combine.
Tip: Urad Dal (whole) requires soaking and a long, slow cooking for best results.
For faster cooking, try moong dal, which doesn't require soaking and cooks much faster.