I used my Instant Pot to cook the dal. Add the rinsed toor dal, 1.5 cups of water, chopped onion and tomatoes, turmeric powder, and oil. Pressure cook for 20 minutes at high-pressure mode and release the pressure naturally.

Mash the dal along with onions and tomatoes and set aside. You can also cook the dal in the stove-top pressure cooker. You can cook for three to four whistles.

Mix 1.5 tsp of tamarind paste with 1.5 cups of water. To this, add the chopped red radish and salt. Cover and cook for 5 to 7 minutes.

Now remove the lid and add the curry leaves. Cook for 4 to 5 more minutes until the radishes are fork-tender.

Now mix 1 tbsp of sambar powder in 1 cup of water without any lumps and add it to the radish mix. Reduce the heat to low, and cook for five more minutes till the raw smell of the sambar powder goes off.

Finally, add the mashed toor dal mix and cilantro.

Bring it to a boil and turn off the heat.

You can prepare the tempering separately. Heat a tempering pan and add 2 tsp oil. When it is hot, add mustard seeds, fenugreek seeds, and asafoetida. Let the mustard seeds splutter and add them to the sambar. That's it. The sambar is ready. Enjoy it with rice idli or dosa.