First, add cleaned and washed toor dal along with 2 cups of water in the inner pot of an IP.
Switch on the IP, and place the inner pot, close the pot with IP lid with valve in sealing position. Press Manual/Pressure Cook and cook the dal on high pressure for 10 minutes.
Once the IP beeps, allow the pressure to release naturally. (It will take anywhere between 15-20 minutes)
Mash the boiled dal using potato masher and transfer it to a bowl. For the next step, either clean the inner pot or use another inner pot if you have it. (I have two steel insert so I quickly proceeded to next step.)
Switch on the sauté mode and heat oil into it. Add mustard seeds and fenugreek seeds, allow them to crackle for few seconds. Take not to burn them.
Add curry leaves and red chilies, fry for few seconds. Add hing (asafoetida) and mix.
Add pearl onions/shallots and sauté for minute.
Add all the vegetable - eggplant, radish, pumpkin, drumsticks and give it a nice sauté for 30 seconds.
Then add chopped tomatoes and sauté for another 30 seconds.
Add turmeric powder, red chili powder and sambar powder and give it a good mix.
Add the boiled dal, salt and mix. Now add tamarind extract (pulp), chopped coriander leaves and 2-3 cups of water, mix. I have added 2 cups of water here.
Close the pot again with IP lid and press manual/pressure cook with valve in sealing position, and allow it to cook on low pressure for 3 minutes. (this ensures that vegetables are cooked through along with the spices and dal, and still remains intact).
Once the IP beeps, allow the pressure to release naturally. Open the pot, dish out and serve steaming hot sambar with idlis, vada, rice or uttapams.