1. Preheat oven to 400 degrees F. Slightly poke the eggplant with a knife. This will help the eggplant not to burst while roasting. Brush oil on the skin.
2. Roast eggplant in the oven for about 10 minutes. When it is done, peel the skin. Mix the tamarind paste, salt, and green chillies, and mash it well.
3. In a sauce pan, add oil . When it is hot, add the black mustard, turmeric powder, and asafoetida. Add the mashed eggplant, turn off the heat and mix well.
4. Remove immediately into a serving bowl. Mix in cilantro. It goes well with rice, chapathi (indian vegan bread) or any type of bread.