Cut the eggplants/brinjals in fairly big pieces and soak in salt water for some time.
Heat oil in a suitable plan and add the onions and minced ginger.
Stir fry for a few minutes till the onions turn slightly brown.
Add the chopped tomatoes, turmeric powder, chilly powder, cumin powder, coriander powder, garam masala/spice powder, pepper and salt and simmer till the tomatoes turn pulpy and the oil separates from the mixture.
Add the eggplant/brinjal pieces and mix well.
Cook covered on low heat till the egg plants turn to pulp.
Remove from heat and mash the cooked eggplants to get a pulp.