Heat a pan. On low to medium flame, roast the spices for the filling one by one. Roast till a nice aroma comes and the spices turn golden brown. Do not burn them. Keep aside and let it cool to room temperature.
Grind half of the spices coarsely and the other half finely.
Wash and pat dry the brinjals thoroughly. Now cut them slowly without breaking them.
Make an x cut at the bottom of the brinjal without breaking it. Retain the stem of the brinjal.
Now, stuff the brinjals with the finely ground powder. Arrange them on a plate and keep aside.
In a pan, add oil. Once hot, add mustard seeds, cumin seeds, curry leaves and finely chopped onion. Saute till onion turns translucent.
Add ginger garlic paste. Saute till raw smell goes. Add the remaining coarse powder and jaggery. Mix well.
Add chilli powder, turmeric powder, needed salt. Mix well.
Add brinjal. Saute without breaking the brinjals.
Add tamarind water and 1&1/2 cups water. Mix and cook covered till done.
Open a couple of times in between and give a stir. Adjust salt and spices if needed.The gravy should reach a thick consistency. Oil will float on top. Taste for salt and spices. Garnish with coriander leaves and serve.