Step 1

Peel and boil the potatoes until tender when pierced by a fork.

Step 2

While the potatoes are boiling, make the dough. Pulse flour and salt in a food processor. With the motor running, add the egg and then cold water. Let the processor run for a minute until the dough forms around the blade. Transfer the dough to a bowl, cover with a tea towel and let is sit for 30 minutes while you start on the filling.

Step 3

Cook the onion in oil over very low heat for 20 minutes until they are caramelised. Mash the potatoes, add butter, onions and mix well, then add salt and pepper to taste.

Step 4

Divide the dough into quarters and form into balls. Take one dough ball and roll it out on a well-floured surface in a thin sheet approximately 1/16" thick. Keep the rest of the dough covered to avoid drying out.

Step 5

Cut the dough into circles with a 2" to 3"cookie or scone cutter. Put a teaspoon of potato filling into each dough circle, slightly off-centre, fold the dough over to form a half-moon shape and pinch the edges shut with your fingertips. For a more attractive look, go over the edge one more time and pinch the edges together using your two fingers and a thumb and twist them to form a ruffled edge.

Step 6

Repeat with the remaining dough circles until you run out of both dough and filling. The recipe should make approximately 65 pierogies.

Step 7

Cook the pierogies in a pot of salted boiling water. Stir to prevent them sticking to the bottom. Once they float to the top, drain and pan fry in butter over medium heat until golden on both sides.

Step 8

Serve with sour cream, dill and crispy fried onions or shallots.