1. Wash the dill and cucumber, chop the dill finely, chop the cucumber on a large grater.
2. Divide the herring into fillets, remove the fins, tail, entrails and head.
3. Beat off the fillet slightly and cover with butter.
4. On top of the oil-a layer of dill, then cucumber.
5. Tightly roll into a roll and wrap in plastic wrap, put in the refrigerator for a few hours.