Clean the fish pieces. In a deep pan add water, cleaned fish pieces, whole garam masala (cinnamon, cardamom, cloves) and salt, let it boil. Reduce heat and cook for 12-15 min. Switch off heat and take out the fish from the broth.
Let the fish pieces cool down and discard skin and fish bones, mash the fish.
In a pan heat 2 tbsp. oil, when the oil is hot add chopped onion. Cook till the onions change color.
Add onion and ginger garlic paste, mix well and cook for 3-4 min.
Add the mashed fish and mix well, cook for 2-3 min. Add soaked bread slices, salt and sugar, mix well.
Add cumin powder, red chili powder, garam masala powder and mix well. Add chopped coriander, and green chilies, mix well.
Let the fish mix cool down. Make round /oval shape with the mixture.
To make the batter, take gram flour, salt and soda bi carbonate in a bowl and mix with some water. In another deep plate keep the breadcrumbs. Dip each round fish balls into the mixture, roll in breadcrumb to coat well. Keep aside. Repeat the process for all other patties.
Dip the coated balls again into gram flour mixture and roll in bread crumbs, one by one.
Heat oil in a deep pan or kadhai and fry the fish croquettes to brown.
Serve hot with tomato ketchup or kasundi (mustard sauce) and onion slices.