Method of Preparation :
Steam fish in a little water with 1/2tsp of turmeric. Remove bones and mash coarsely. Grind ginger and garlic and keep aside.
Heat mustard oil and sauté onions till done. Add ground ginger-garlic paste and chilli powder. Fry well and add sugar, salt and fish. Stir continuously till the mixture becomes dry. Add garam masala and remove from fire.
Sieve the flour and salt together. Rub in the ghee till the flour resembles coarse breadcrumbs. Prepare a medium soft dough with water. Make small balls from the dough and roll into thick puris. Put 1 heaped tablespoonful of filling in the centre of each puri. Seal the edges and roll again into a puri. Take care not to spill the filling.
Heat groundnut oil and fry puris, one at a time till golden colour.