Peel the onion, cut into fine cubes. Also finely dice the bacon and fry in hot fat.
Sauté the onion cubes in it as well until translucent. Allow to cool.
Peel potatoes and grate coarsely.
Mix 2 egg yolks and whipped cream. Mix potatoes, egg yolk-whipped cream, bacon, chives, parsley, onion, spices and mix everything well.
Roll out puff pastry (not too thin) with potato mixture and roll up.
Brush the edges of the dough with egg, place the strudel, seam side down, on a baking sheet lined with parchment paper.
Brush with remaining egg yolk. Poke a few holes in the dough.
Bake for 10 minutes at 200 °C and another 10 minutes at 175 °C.
Cut the strudel into slices and serve, for example, with leaf salad.