Wash the pork schnitzel, pat dry and pound it flat in the cut freezer bag. Brush with mustard and season with salt and pepper. Season a little carefully because the other ingredients are also flavorful.
Brush the schnitzel with mince and top with slices of cucumber cut lengthways. Roll up and close with roulade needles.
Cut the onion into cubes. In the meantime, heat the oil in a pan and fry the rolls on all sides. Roast the onions and fry everything for about 20 minutes over low heat.
Enjoy with salad and fresh bread or baked potatoes.