Wash brinjals and wipe them with a cloth.
If the brinjal stalks are green and fresh then don't remove them but if they are dry or discolored then remove them.
With a sharp knife make 2 or 4 slits in the brinjals .
Heat oil in a heavy and broad pan till it come to a smoking point (if you are not using mustard oil then skip this step) then let it cool down a bit.
Stuffing - In a bowl add mango powder,salt,turmeric, coriander powder, chili powder, crushed fennel and asafoetida.
Add 2 tbsp warm oil in the spices and mix, now add chopped fresh coriander and mix properly.
Stuff the brinjals with this prepared stuffing spice mix.
Add cumin seeds in the oil and when seeds start crackling add pinch of turmeric and 1/4 tsp salt and mix .
Add the stuffed brinjals in the pan (in which we have heated the mustard oil)
Sprinkle 2 tbsp of the remaining stuffing masala over the brinjals.
Cover the pan with a lid and cook on low heat.
If you have some left over stuffing mixture then you can stuff it in green chilies or thick potato roundels and cook them with brinjals.
Gently stir and turn the brinjals 2-3 times and cook till done.
Serve with roti, poori or daal -rice combo.