Prep the brinjal by removing the stalk, washing. Chop each into half, then slice each into lengthwise. Keep it soaked in water to prevent browning.
Heat a nonstick pan with cooking oil and add all the seasoning ingredients one after the other. When the mustard starts spluttering, drain the brinjal from water and add to the pan.
Add turmeric powder, jaggery if adding, and salt. Give a quick stir.
Cover the pan with lid and cook for about 5 minutes. Soak tamarind in warm water for about 5 minutes. Squeeze thick tamarind juice.
The eggplant slices would have turned soft now. Add the thick tamarind juice and rasam powder.
Stir and cook for 3 more minutes or till the tamarind water is absorbed by the veggie.
Switch off the flame. Eggplant dry curry in typical Udupi style is ready. Serve it with steamed rice and relish.