Rinse the rice and lentils and drain well.
Add this to the inner lining pot of the Instant Pot. Add the vegetables to it.
Also add in the turmeric powder, sambar powder and salt to it.
Soak the tamarind in ¼ cup water and squeeze the pulp out of it well. Strain and pour this to the rice and dal. Add another ¼ cup water and repeat.
Add 4 cups water more to the Instant Pot inner liner and mix well.
Close the Instant Pot. Put the sealing knob in "sealing" position. Press the MANUAL button and adjust time to 10 mins.
Once cooking for 10 mins is done, wait for the little steel knob next to the sealing knob to fall down. That is when you know that all the pressure is released (NPR - natural Pressure release). This should take about another 10 mins.
Meanwhile in a small sauce pan, heat the oil on the stove top. Add the mustard seeds and let it splutter. Add the asafetida and curry leaves, mix well and pour on to the sambar rice in the Instant Pot.
Garnish with the chopped cilantro.
Serve hot with papaddums, yogurt / raita and Indian pickle.