Ingredients CardPierogi Ruskie110 pierogi · about 4.2 kg Potato and Cheese Filling 2.2 lbfloury potatoes, peeled1.32 lblarge onion, finely chopped¼ cupbutter1.32 lbfull-fat twaróg (Polish farmer's cheese)1 tspsalt1 tspground black peppersalt for the potato water, to taste Dough 8 cupsall-purpose flour1 tspsalt2 ⅛ cupshot water½ cupcanola oil Shaping, Boiling and Frying 2onion, chopped¼ cupbutter17 cupswater 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)