Heat oil in a deep wok and saute onions till they turn lightly brown. Add in ginger and garlic paste, and fry for a minute to blend well.
Add in spices, salt and tomato paste, and fry for another minute mixing everything together.
Add in tomatoes and cook, stirring occasionally till all the moisture evaporates and starts to turn into a thick sauce.
Add in the mushrooms and mix well. Let the mushrooms cook through, until all its water dries up. Garnish with fresh coriander leaves and serve warm.