Put the butter in a warm place so that it becomes soft.
Cut the onion into rings, marinate – I poured boiling water over it, put it in a jar, there salt, sugar, sunflower oil, a little vinegar. Shake it up. Put it in the refrigerator.
Choose the herring that you like.
Chop the butter and herring through a meat grinder.
Mix the minced meat.
Cut white bread into thin slices, cut out circles (or squares, triangles… only cut the cake).
Fry on 1 side, cool.
Put cucumber slices on the bread.
Squeeze the chopped herring out of the culinary syringe beautifully, decorate with herbs. Serve the onion separately.