Roll two strips from puff pastry, about 1/2 cm / 0.2 in thick, 15 – 30 cm / 6 – 12 in long. Make one strip 10 cm / 4 in and one strip 20 cm / 8 in wide. Ends of the strips should be made oval or straight. Put the narrow strip in the middle of a baking sheet and cover it with thin blinis so that the stuffing doesn’t make the dough soggy.
Put stuffing made from vyaziga (dried spinal cord of sturgeon) about 6-7 cm / 2.4-2.8 in wide on top of blinis. On top of vyaziga put pieces of boiled sturgeon, salmon and then cover with another layer of vyaziga. Cover stuffing with blinis, moisten with beaten eggs on the sides, bind them with edges of blinis on the bottom, moisten edges of puff dough around stuffing with beaten egg, cover with wider strip of dough and press edges of strips together.
Kulebyaka can be decorated with a decoration or with narrow strips made from leftover puff pastry. Moisten one side of decorations with whipped eggs and attach them to the kulebyaka. Edges of kulebyaka can be covered with a dough strip. Trim, moisten with whipped egg, make punctures on ends with a knife to let steam escape and place in hot oven for 40-50 minutes. If kulebyaka is browned on top but is not ready on the sides, cover the browned part with paper, moistened with water on the outer side. If the bottom of kulebyaka is not ready yet, place baking sheet on a stove that’s not very hot.
Kulebyaka with rice and fish, meat, offals, cabbage, etc., can be prepared the same way.
Serve kulebyaka with caviar, butter and ukha.