Ingredients CardPierogi Ruskie110 pierogi · about 4.2 kg Potato and Cheese Filling 1000 gfloury potatoes, peeled600 glarge onion, finely chopped4 tbspbutter600 gfull-fat twaróg (Polish farmer's cheese)1 tspsalt1 tspground black peppersalt for the potato water, to taste Dough 1000 gall-purpose flour1 tspsalt500 mlhot water8 tbspcanola oil Shaping, Boiling and Frying 2onion, chopped4 tbspbutter4 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)