Marinate the fish with salt and a pinch of turmeric powder. Keep aside.
Heat oil in a frying pan, fry the fish till light golden. Keep aside on a kitchen absorbent towel.
To the same oil, add the onion paste, a pinch of salt and sugar, cook till the paste turns a gorgeous golden brown and the onions are cooked. Stir in the ginger paste, green chili paste, turmeric powder and red chili powder, cook over a medium flame till the masala starts to release oil.
Add 1/2 cup of warm water and gently place the fried fish in the pan. Cook for 5-7 minutes over a low flame.
Pour in the orange juice, sprinkle in the salt and sugar, throw in the green chilies. Give it a hearty stir.
Add the orange segments and simmer for a further 3-4 minutes till the gravy has slightly thickened.
Adjust seasonings and serve hot.