A fish fry or diamond fry in Calcutta is a crumb-coated fillet of bhetki—something that would be called a fish cutlet elsewhere. Fish fry and fish kabiraji are served by cabin-style restaurants, small take-away shops, street food vendors, as well as in catered events such as weddings.

Calcutta has no dearth of good fish fries. Some of the ones we love include Badshah (Jadavpur), Mitra Cafe (Sobhabazar), etc. For this recipe, we wanted to recreate our favourite fish fry, which comes from a shop named Apanjan (আপনজন) in Kalighat. Apanjan's large fish fries are even bigger than the size we ended up using.

We received a lot of technical inputs from Saptarshi's jethu (uncle) Sujit Chakraborty—who besides being a great cook, has been running a catering business for the last 30 years.

Over the course of testing this recipe, we visited several markets in Calcutta. If you want bhetki fillets the best place to go to is Fish Range, New Market. All the shops out there are very good, but the one we ended up purchasing our fillets from was called A.K.G. & Co. The owner, Atanu Gurey, was patient and helpful, and his staff adept at creating perfect, uniform rectangles of fish exactly to our size specification. We have shown the whole process of filleting the whole bhetki both for documentation, and for anyone who may be interested in learning to do it themselves.

Following jethu's suggestion we kept our marinade simple, using only green chillies, coriander and flat-leaf or Italian parsley. We also tried adding mint, but preferred the version without better. You are, however, free to play around with the flavours as long as you keep the ratio of the marinade to the fish constant.

Those who want to take their fish fry game a notch further can try their hand at fish kabiraji, which is nothing but fish fry encased in a fine web of egg batter.