Pressure cook the lentils (toor dal) in a pressure cooker alongwith 6 cups of water until the lentils are tender.

Heat oil in a pot on medium-high flame.

Once it's hot, add mustard seeds, methi seeds and cumin seeds.

Allow to splutter and crackle.

Once they stop doing so, add in the curry leaves and ginger.

Stir-fry for 5 minutes until the raw smell of ginger is gone.

Add asafoetida powder and continue to stir-fry for another 5-7 minutes.

Toss in the green chillies, mix well and continue to stir-fry for another 2-3 minutes.

Then add in the tomatoes and 1/4 cup of water to cook the tomatoes.

Mix well and cook on high flame until the tomatoes are softened.

Add salt, red chilli powder and turmeric powder.

Mix well.

Extract tamarind pulp from tamarind to use as tamarind water.

To do this, soak about 3 inches piece of tamarind in 1 cup of hot water.

Squeeze to extract the tamarind pulp and let it mix with the water to form'tamarind water

There is no need to pass this through a strainer- use it directly!

Measure out 2/3 cup of tamarind water in a cup and add this tamarind water to the tomato mixture.

Mix well and allow it to cook on medium-high flame for 5 minutes.

In the meantime, open the pressure cooker (by this time the lentils will be tender and the whistle would have blown) and with the help of a beater/mashing tool (we use what we call a'mandira' in Hindi. This is a long wooden spoon with a round base that we use for mashing lentils, bananas, etc), in round circular motions, mash the lentils completely, until they mix with the water in which they were being cooked.

Now add 5 cups of water alongwith the lentil and water mixture that was used to cook the lentils. Add the tamarind-tomato mixture, mixing gracefully, as you sing your favourite kitchen song side-by-side!

Allow this to come to a boil.
Lower flame and cook for 10 more minutes on a simmer.

Remove from flame and serve immediately with cooked long-grain white Basmati rice.