Cut the potatoes into rings, as wide as a peeler, and then peel the potatoes into long strips. Afterwards wind them up and pierce transversely with a roulade needle. Then cook the potatoes in salted water with bay leaves and allspice for 15 minutes at low heat. Now take it out of the water and drain on a kitchen towel. Separate the eggs and lightly whisk the egg yolk with a little salt. Now heat the canola oil in a pot (at least twice as high as with oil) and fry the potatoes for 1 min. Then remove from the oil, remove the roulade needles and halve them. Bake again in the oil until they are golden colored. Finally, drain on a kitchen towel and salt lightly. To serve, place the potatoes on a plate, pour the egg yolk over it and add the caviar on top.