1Rinse the yellow lentils (toor dal) thoroughly under running water.
In a pressure cooker, add the rinsed lentils, chopped tomatoes, chopped onion, chopped green chili, turmeric powder, and 4 cups of water.
Close the lid of the pressure cooker and cook on medium heat for about 3-4 whistles or until the lentils are soft and cooked.
Once the pressure releases naturally, open the lid and mash the cooked lentils slightly with a ladle.
In a separate pan, heat 1 tablespoon of oil over medium heat.
Add mustard seeds and let them splutter.
Add cumin seeds and curry leaves, and sauté for a few seconds until fragrant.
Pour the tempering (oil with mustard seeds, cumin seeds, and curry leaves) into the cooked lentils.
Add salt to taste and mix well.
Simmer the dal for a few more minutes to let the flavors meld together.
Serve hot with rice or roti.