For the Bockwurst in potato puff pastry coat, wash the potatoes, boil, peel and allow to steam off completely. Chop the onion, dice finely and sauté with 1 tablespoon of butter in a small pan, until translucent, let cool slightly.
Cut the bockwurst in half. Cut a piece of puff pastry according to the size of the bockwurst. Mix the eggs, brush the puff pastry with some of it.
Coarsely mash the potatoes, fold in the sour cream and eggs (save some to coat the patties). Mix in onions, plenty of ground salt and pepper, and a few dashes of Worcester sauce.
Put some mixture on the puff pastry, put half of the bockwurst on top, put a slice of cheese on top, put the other half of the bockwurst on the other side, and add potato mixture again.
Overlap the puff pastry to form a parcel, brush with leftover egg. Carefully prick the top of the parcel with a fork to allow the puff pastry to rise nicely.
Be sure to put it back in the fridge so that the puff pastry gets nice and cold again. Directly from the refrigerator, on a baking sheet lined with baking paper, bake in an oven preheated to 200 degrees for about 15 – 20 minutes.
Arrange on a plate and serve.