Wash the masoor dal in clean water and soak for 5 to 10 minutes.
Now, heat oil in a pressure cooker and add cumin seeds to sizzle over medium heat.
After that, add the chopped onion and saute until golden.
When the onion gets golden, add tomato puree and green chillies.
Then add salt and turmeric powder, mix them well, and saute until aromatic.
When the masala releases oil, add the soaked masoor dal.
Pour 2 cups of water and mix well.
Cover the cooker with the lid and cook over high heat for 2 to 3 whistles, then turn off the flame.
When the pressure is released, the dal is soft and completely cooked.
Now add garam masala and mix well in the dal.
Serve with roti and steamed rice.