Heat 1tbsp oil in a pan; add chana dal, urad dal, cumin seeds and dry red chilies. Cook till the dal is golden and chilies turn a dark color. Remove onto a plate.
In the same pan, add the chopped eggplant, tomato and the green chilies. Cover and cook till the eggplant is cooked through and tender. Turn off the heat and set aside to cool.
When cool enough to handle, grind the dal mixture first into a somewhat smooth powder. Add the cooked eggplant mixture, salt and tamarind paste and grind to a smooth paste. You can leave it a little chunky, if you like texture in your chutney.
Remove the chutney into a bowl.
Heat 1tsp oil in a small pan, add the urad dal, mustard seeds and curry leaves. Once the seeds start to splutter, add it to the chutney and mix well. Serve with rice, upma, idli, dosa or even roti.