Wash the brinjal, wipe dry it.
Apply little oil on its surface all around and roast it over the flame, turning around on the fire, till whole of its outer surface turns blackish and flaky.
Peel off the burnt skin of the roasted brinjal.
Add onion, ginger, garlic, dhania patta, salt, and uncooked mustard oil.
Mash everything well, leaving no lumps of unmashed baingan.
Serve with dal-rice, khichdi or stuffed parathas.