Place fish, egg, cornflour, tamari, fish sauce, garlic, ginger, lime leaves, lemongrass, coriander stalks and leaves, chili flakes and salt in the bowl of a food processor.
Process briefly until the mixture comes together but is still a bit chunky.
Roll the mixture into 10-12 rounds and flatten each to resemble a fishcake.
Heat a large frying pan on medium. Drizzle about half a tablespoon of olive oil in the pan. Place half of the fishcakes in the pan. Reduce heat to medium-low. Cook each side for approximately 5 minutes until both sides are cooked and golden. Press down on the fishcakes with a spatula during cooking.
Repeat with the remaining fishcakes.
Serve in lettuce leaves with Thai sweet chili sauce on the side.
Notes
Ginger And Garlic - It is important to mince the garlic, grate the ginger and chop the lime leaves, lemongrass, and coriander. This is because the fish chops and comes together very quickly in the food processor and if you don't prep, chop and mince the other ingredients; you will be left with chunky pieces of garlic or lemongrass while the fish is completely pulverized.
Cleaning - When you finish processing the fish mixture, immediately clean the bowl of the processor by filling it with hot water and scraping off bits of the mixture stuck to the sides and blades. If you don't do this, the fish and cornflour mixture will dry and be pretty much impossible to clean.