Poach the fish in salted water with vinegar (2-3 tbsp of vinegar to about 1 litre of water) at a gentle simmer for 10-15 minutes until cooked through and flaking easily.
Leave to cool, then carefully remove the bones and cut the flesh into cubes.
Pile it high on a glass or china platter.
Coat it generously with the mayonnaise.
Cut the hard-boiled eggs into wedges and arrange them around the fish salad.
Garnish with lemon slices.
Put fresh lettuce leaves all round.
Serve cold.
Based on: A jó házikonyha (a classic Hungarian cookbook), modernised. Calories and protein are estimated.