Ingredients CardPierogi Ruskie110 pierogi · about 4.2 kg Potato and Cheese Filling 1000 gfloury potatoes, peeled600 glarge onion, finely chopped60 mlbutter600 gfull-fat twaróg (Polish farmer's cheese)5 mlsalt5 mlground black peppersalt for the potato water, to taste Dough 1000 gall-purpose flour5 mlsalt500 mlhot water120 mlcanola oil Shaping, Boiling and Frying 2onion, chopped60 mlbutter4 lwater for boilingsalt for the water, to taste Safety: Large batch: cool quickly in shallow containers or an ice bath, to below 5 °C within 6 hours, before refrigerating. (USDA FSIS)