1. Make the tartar sauce
Combine all the tartar sauce ingredients in a bowl and mix until well combined. Cover and refrigerate until ready to serve.
2. Crumb the fish
Place the flour, eggs, and panko breadcrumbs into three separate shallow bowls or trays. Lightly coat each piece of fish in the flour, dip into the egg, then coat in the breadcrumbs. Repeat the egg and breadcrumb step once more to create a double coating. Place the crumbed fish onto a tray.
3. Preheat the oven
Preheat the oven to 180°C.
4. Fry the fish
Fill a wok or deep frying pan with vegetable oil to about one-third full and heat to 165°C, or until bubbles form around a wooden spoon when dipped into the oil. Carefully add two pieces of fish and fry for 4–5 minutes, turning every 30 seconds, until golden and crisp. Transfer to a paper towel-lined tray, season lightly with sea salt, and keep warm in the oven while frying the remaining fish.
5. Assemble the burgers
Place a slice of cheese on the base of each bun, top with a hot piece of fish, and spoon over generous amounts of dill tartar sauce. Add the bun tops and serve immediately.
Optional additions
Shredded lettuce, sliced pickles, or a squeeze of lemon all work beautifully if you want to customise your burger.