Peel and cut potatoes into small pieces. Cover with water and cook until easily pierced with a fork. Drain (reserving 1 cup water for dough) and mash well. I use a potato rice.
Meanwhile sautee onion in oil for about 7 minutes over meadium heat. Once onions are done, combine salt pepper, potatoes and onions and mix well. You can add a bit of well drained sauerkraut if you would like.
To Make Dough:
Combine flour, salt, oil and reserved water in large bowl, and mix until dough forms a ball. If dough is dry, add more water, 1 tablespoon at a time, until moist. If dough is sticky, add more flour, 1 tablespoon at a time, until it's smooth.
Put it all together!
Roll the pierogi dough on a floured board or countertop until 1/8" thick. Cut circles of dough with a cookie cutter or drinking glass. Place a small ball of filling (about a tablespoon) on each dough round and fold the dough over, forming a semi-circle. Press the edges together with the tines of a fork.
Boil the perogies a few at a time in a large pot of water. They are done when they float to the top (about 8-10 minutes). Rinse in cool water and let dry.
If you want to pan fry them, can a "healthy" pat of vegan butter to a pan, wait for it to melt and them fry on each side until golden.