Coarsely chop the pistachios. Squeeze the sausage meat out of the sausages and mix with the pistachios. Wash the parsley, dab dry and pull the leaves from the stalks. Put the schnitzel roulades on a large board, flatten and cut in half crosswise. Season the roulades with pepper and a little salt and spread a thin layer of sausage meat. Place parsley leaves, except for a few for garnishing, on the meat mixture.
Roll up the meat and fix it with wooden skewers. Peel and finely dice the onions. Heat the oil in a pan and fry the rolls vigorously while turning. Add half of the onions, braise briefly and deglaze with stock and brandy. Bring to the boil and braise covered for about 10 minutes. In the meantime clean, wash and drain the peppers. Cut the pepper halves into fine strips on a kitchen slicer. Heat the fat in a pan. Braise the paprika and remaining onions for 2-3 minutes, season with salt and pepper and keep warm. Lift the rolls out of the stew and keep them warm as well. Add the sauce thickener to the stock while stirring and bring to the boil again briefly. Season to taste with pepper and brandy.
Cut the pepper halves into fine strips on a kitchen slicer. Heat the fat in a pan. Braise the paprika and remaining onions for 2-3 minutes, season with salt and pepper and keep warm. Lift the rolls out of the stew and keep them warm as well. Add the sauce thickener to the stock while stirring and bring to the boil again briefly. Season to taste with pepper and brandy. Arrange the paprika vegetables with the rolls and sauce on plates. Serve garnished with parsley