To start making Kerala Cheriya Ulli Sambar, in a pressure cooker add dal with a cup of water and turmeric powder. Pressure cook the dal for a couple of whistles. After a couple of whistles, turn the heat to low and simmer for 2 to 3 minutes and turn off the heat. Allow the pressure to release naturally. 

Once the pressure is released, open the cooker and mash the dal with a potato masher or whisk the dal to make it lightly smooth. 

Next in a small pan over medium heat, roast the coconut for a few minutes and grind it into a smooth paste. Keep aside.

In a saute pan add a tablespoon of coconut oil and add shallots/small onions with a little salt, curry leaves, green chili and saute until translucent and slightly brown. Add the tomatoes, turmeric powder, sambar powder,salt and tamarind water to the onion mixture and bring this sambar mixture to a boil Turn the heat to low and simmer the ulli sambar mixture for about 3 to 4 minutes.

After  few minutes, add the whisked dal and the coconut paste and give it a stir. Bring the mixture to a simmering boil for another 3 to 4 minutes. Check the salt and spice levels and adjust to suit your taste.

Transfer the Ulli Sambar to a serving bowl. The final step is to make the seasoning. In a small tadka pan, heat  a teaspoon of coconut oil. Add the mustard seeds and allow it to crackle. Add the remaining ingredients and roast for about a minute until the aromas come through.

Pour the seasoning to the Ulli Sambar, add the chopped coriander leaves and give the sambar a stir.

Serve the Kerala Cheriya Ulli Sambar along with hot steamed rice, topped with ghee and a vegetable like Kerala Vendakkai Thoran.