Ingredients CardPierogi Ruskie27.5 pierogi · about 1 kg Potato and Cheese Filling 250 gfloury potatoes, peeled150 glarge onion, finely chopped1 tbspbutter150 gfull-fat twaróg (Polish farmer's cheese)¼ tspsalt¼ tspground black peppersalt for the potato water, to taste Dough 250 gall-purpose flour¼ tspsalt125 mlhot water2 tbspcanola oil Shaping, Boiling and Frying ½onion, chopped1 tbspbutter4 lwater for boilingsalt for the water, to taste