Method Put the washed lentils in a pan with the water and the turmeric. Simmer for about 15 minutes until cooked, then salt to taste. While the dahl is cooking, fry the cumin seeds in a little oil, then add the chopped onion and soften. Add the crushed garlic and chopped tomato and fry for a minute. Finally add the fried cumin, onion tomatoes and garlic to the dahl and serve.