Pierogi Ruskie

Step 1

Mix flour and salt in a large bowl. Make a well, add egg and sour cream, and stir until shaggy dough forms.

Step 2

Knead on a floured surface for 5 minutes until smooth and elastic. Rest 10 minutes covered.

Step 3

Boil potato in salted water until fork-tender, about 12 minutes. Drain well and return to pot.

Step 4

Mash potato, stir in cheese, salt, and pepper. Cool for 5 minutes.

Step 5

Heat 1 tablespoon butter in a skillet over medium. Cook onions, stirring often, until golden brown, 8–10 minutes. Set aside.

Step 6

Roll dough 1/8-inch thin on a floured surface. Cut 3-inch circles with a glass or biscuit cutter.

Step 7

Place 1 tablespoon filling on each circle. Fold in half, press edges, then crimp with a fork to seal.

Step 8

Bring a large pot of salted water to a boil. Add pierogi in batches and stir gently.

Step 9

Boil until they float, then 2 minutes more. Remove with a slotted spoon to a plate.

Step 10

Heat remaining 2 tablespoons butter in the skillet over medium-high until foaming.

Step 11

Pan-fry pierogi in batches until golden and crispy on both sides, about 3 minutes per batch.

Step 12

Serve hot topped with caramelized onions and a dollop of sour cream.