sentence: add water and flour into a bowl and mix sentence: peel a potato and place in a pot of boiling water sentence: chop an onion into thin pieces sentence: mash the potatoes with a masher sentence: add the potatoes onions cheese salt and pepper into a bowl and mix sentence: roll the dough into a thin sheet sentence: cut the dough into circles sentence: place the filling at the center of the dough and close it sentence: place the pierogis in a pot of boiling water sentence: fry some onions and add them to a plate of pierogis