What you need:
3 cups of flour
1/2 cup of vegan sour cream
The equivalent of one egg with egg replacer (Ener-G makes a really good one)
Silk creamer
Five medium size yellow potatoes
Half of a red onion
A few tablespoons of butter replacement
A little salt, and a little pepper.
First, boil the potatoes. It'll take about twenty minutes for them to become soft enough to mash easily.
Next, combine the four, sour cream, and egg replacer in a bowl and knead until it turns into a stretchy dough. Cover that with plastic wrap (make sure the wrap is directly on the dough, or else it'll get hard) and put it in the refrigerator.
Then, put two tablespoons of butter replacement in a frying pan. Chop half of the onion into small pieces, and fry until golden brown. The potatoes should be done boiling, at this point, so take them out of the water and mash them in a bowl. (I keep the skins on, for extra flavor) Pour the Silk creamer into the potatoes while mashing them, until you get a thick paste. Once the onions are done, blend them in with the potatoes, along with a little bit of salt and pepper.
Now, the difficult part. Put another pot of boiling water onto the stove. Take the dough out of the refrigerator, and start forming little pancakes with it. The size of your pierogi doesn't matter; I tend to make them a bit bigger than most people. Put a spoonful of your potato-onion mix into the center of the dough pancake, and fold the pancake into a half circle. Pinch the edges to seal it. Putting a little bit of water on the edges before sealing helps a lot in getting it to stick together. MAKE SURE IT IS COMPLETELY SEALED. Toss your pierogies into the boiling water, and allow them to cook until they float. Then, in a frying pan with more butter replacement, fry the boiled pierogies until they turn gold.
Good luck!