2 cups all-purpose flour, plus extra for preparing dough
1/2 teaspoon salt
1 large egg, beaten
1/2 cup sour cream
1/4 cup butter, softened and cut into small pieces
5 large red potatoes
2 large onions
4 Tablespoons butter
4-8 oz. grated cheddar cheese
salt and pepper to taste
1/4 cup chopped fresh parsley
extra sour cream to serve
Prepare the Dough:
Combine flour and salt in a large mixing bowl. Combine the egg and sour cream in a separate bowl and combine it well. Add wet to dry ingredients with 1/4 cup of the softened butter pieces and work until the dough loses most of its stickiness (about 5-7 minutes).
You may use a food processor with a dough hook for this, but be careful not to overbeat.
Wrap the dough in plastic and let rest in the refrigerator for 20-30 minutes or overnight.
Prepare the Filling:
Peel and boil potatoes until soft.
While the potatoes are boiling, finely chop one of the onions and saute in 2 tablespoons of butter until soft and translucent. Drain potatoes and remove to a large mixing bowl. Add the sauteed onions. Mash the potatoes and onions together with a potato masher. Add grated cheese. Salt and pepper to taste. Mix in parsley. Let the mixture cool and then form into 1" balls.
Prepare the Pierogies:
Roll the pierogy dough on a floured board or countertop until 1/8" thick. Cut circles of dough with a cookie cutter, a wide-mouthed drinking glass or a clean empty food can. Place a ball of filling on each circle of dough and fold the dough over, forming a semi-circle. Press the edges together with the tines of a fork. Boil the pierogies 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. Finely chop the remaining onion and saute in 2 tabelspoons of butter in a large frying pan until onions are translucent. Add pierogies and pan fry until lightly crispy. Serve with sour cream.