Marinate the fish with a little turmeric powder and salt.
Heat 1 tbsp mustard oil in a pan, shallow fry the fish. Allow to cool to room temperature. Debone the fish, lightly mash and keep aside.
Heat the remaining mustard oil and 1 tbsp ghee in a separate pan. Throw in the bay leaves.
Add the potatoes, radish and cauliflower florets, sprinkle in the the turmeric powder, red chilli powder and salt, stir fry over a high flame for 4-5 minutes. Now add the eggplant, continue to stir fry over a medium flame for another 5 odd minutes.
Stir in the whipped yoghurt, add the ginger paste and sugar, give it all a hearty mix. Continue to cook till all the vegetables are tender.
Add the fish, give it another hearty mix. Cook over a low flame till almost dry.
Adjust seasonings. Finish with a dollop of ghee and a pinch of garam masala powder. Serve hot.