Pre-heat the oven to 200°C. Roll out the puff pastry on the work surface and cut into rectangle strips (they should be as long as the Tiny Hot Dogs and wide enough to wrap around the sausages once).
Wash the sauerkraut with cold water and drain thoroughly.
Place some sauerkraut in the middle of the puff pastry bits, add a sausage in the middle and spread some mustard on the sausage. Then roll up the pastry.
Bake in the oven (30-40 minutes, depending on your oven) on a baking tray (covered with baking paper).
Let the sausage rolls cool down before serving!