Place fish in a bowl. Apply ¼ tsp turmeric powder and salt and set aside to marinate for 15 minutes.
Heat 2 tbsps oil in a non-stick wok. Place marinated fish pieces in the wok, cover and cook for 4-5 minutes. Flip and cook on the other side for 4-5 minutes. Switch off heat.
Heat remaining oil in a non-stick pressure cooker. Add sugar and saute till light brown. Add paanch phoran and sauté till fragrant. Break the dried red chillies and add. Add ginger and garlic and sauté for 1-2 minutes.
Finely chop onions in a chopper, add to the cooker and sauté for a minute.
Peel and roughly chop the parval and add to the cooker.
Slit brinjals, add to the cooker and sauté for a minute. Add red chilli powder, garam masala powder, a pinch turmeric powder and cumin powder sauté for 1-2 minutes.
Cut tomatoes into small cubes, add to the cooker and sauté for a minute.
Add Bengal gram, salt, 3 cups of water, potato, pumpkin, banana and cook on high heat till 2 whistles are given out. Switch off heat. Open the lid when pressure reduces completely. Cook on low heat till the gravy thickens.
Place a round mould on a serving plate. Place the vegetables in the mould. Press lightly and remove the mould. Place a piece of fish on top. Garnish with a lemon wedge and a coriander sprig and serve hot.