Wash brinjal and pat dry it in kitchen towel. Remove green part of the stem. Partially slit brinjal into 8 sections in the middle keeping them intact together at the stem.
Heat oil in a wide pan.
Fry brinjal in oil until the outer skin begin to wilt. Brinjal should be almost cooked. Drain it off from oil and set aside.
In the same pan (add more oil if brinjal suck up all the oil) crackle mustard seeds and cumin seeds.
Add onions and saute until translucent. Add curry leaves and kosher salt. Mix.
Fry minced ginger garlic in the pan for 2 to 3 minutes.
Add the masala paste along with red chili powder, turmeric powder, garam masala powder, and cook for 1 to 2 minutes.
Pour ¼ cup water and bring it to boil.
Add tamarind paste and stir.
Once gravy starts to boil, add in fried brinjal. Let it cook for 3 to 5 minutes on medium flame until combined. If gravy is too thick add extra water accordingly to adjust the consistency of the curry.
Brinjal will be wilted completely once fully cooked.
Remove from heat. Garnish with chopped coriander leaves and serve hot with pulao, biryani, roti.