Clean the fish fillets and make a shallow cut down the middle, then fold them so they are double the thickness. Season with salt and pepper.
Whisk the water and flour together to form a thin, smooth batter; dip the fillets in the batter so that only a thin layer clings to them, then coat them in the panko breadcrumbs.
Heat a large frying pan and fry the fillets in butter and oil – possibly in two batches, for about 2 minutes on each side, until they are crisp and golden. Leave them to drain briefly on kitchen paper.
Finely chop the gherkins on a chopping board with a knife, or pulse them briefly in a food processor.
Mix the gherkins and mayonnaise together and season with salt and pepper.
Rinse the leaves and sprigs, then gently toss them with oil and lemon juice.
Spread butter on the rye bread, place two warm fish fillets on top, then add a generous spoonful of remoulade and finish with the herb salad and a few pickled onions. Serve with lemon wedges to squeeze over the top.
P.S. You can also order this dish from Aamanns Deli & Takeaway HERE
