Create the burger dressing by mixing the mayonnaise, mustard, chopped capers, finely chopped dill, chopped spring onion, salt, pepper, and sugar.

Set up the breading station: flour, beaten egg, and breadcrumbs. Add a pinch of salt and pepper to each.

Add a pinch of salt and pepper to the fish and then roll the fillets through the flour, then the egg, and finally the breadcrumbs.

Place a pan over medium-high heat and add 1 cup of oil to it.

When the oil is hot, add the fish and fry on one side until golden, and then flip and cook on the other side until golden and cooked through. For a fish like the basa pictured here, it only takes about 3 minutes per side. If you’re using thicker fillets, you may have to increase the time and maybe lower the heat so that the outside doesn’t burn while the inside cooks.

Remove the fillets to a cooling rack or plate with paper towels on it to absorb the oil.

(Optional) – Toast the burgers (face down) in a dry pan over medium heat (about a minute or so). You don’t need any butter or oil if using brioche buns.

Assemble the burgers: toasted bun, crispy fish, a couple tablespoons of the burger dressing, a thick slice of tomato, and a couple of leaves of gem lettuce.