2 large fresh herring, 600 g potato, 2 egg whites, 4 tablespoons oil, 2 tablespoons of flour.
1 cup of water with vinegar, salt, 1 tsp sugar, pepper, parsley, bay leaf, onion, rosemary, a cup of sour cream, 50g butter, 50g grated cheese.
The fish should be prepared the day before, clean the herrings, remove the heads and bones, season, roll on the album, then in flour and fry.
To prepare the marinade: Put to boil for about ten minutes the water acidulated with the chopped onion thinly, sugar, parsley, bay leaf, rosemary and pepper.
When cool, pour this marinade over the fish and refrigerate until the next day.
The next day, cook potatoes in salted water. Drain, let cool, slice and line them with the bottom of a buttered baking dish, arrange on a layer of fish, drained and chopped, a layer of cream and then cover with a layer of potato.
Sprinkle with grated cheese and butter, and go in the oven for about twenty minutes.