Put 150 g of potato salad in the middle of the plate. Left and right of it each 75 g herring salad and meat salad. Mix the mayonnaise with the yoghurt and add a little more water if necessary. A semi-liquid sauce should be created. Halve the hard-boiled eggs and place three half eggs with the yolk side up on the potato salad. Pour the mayonnaise over the eggs and garnish with salmon substitute schnitzel, caviar, half pickles (cut into fans) and parsley.