Polish Potato and Cheese Pierogi

Instructions

1. Prepare the dough
   In a large bowl, mix flour and salt. Make a well in the center and add egg, sour cream, and softened butter. Mix with a fork until combined, then knead with your hands until the dough comes together (about 5-7 minutes). If too sticky, add more flour; if too dry, add a little water. Cover with plastic wrap and let rest for 30 minutes.
2. Make the filling
   While the dough rests, place potatoes in a large pot with salted water. Bring to a boil and cook until fork-tender, about 15 minutes. Drain well and mash until smooth. In a separate pan, sauté diced onion in 2 tablespoons butter until translucent. Mix the onions, farmer's cheese, salt, and pepper into the mashed potatoes. Let the filling cool completely.
3. Form the pierogi
   On a floured surface, roll out the dough to about 1/8 inch thickness. Using a 3-inch round cutter or glass, cut out circles. Place a tablespoon of filling in the center of each circle. Fold the dough over to create a half-moon shape and pinch the edges firmly to seal. Use a fork to press the edges for a decorative finish.
4. Cook the pierogi
   Bring a large pot of salted water to a gentle boil. Cook pierogi in batches of 6-8 for 2-3 minutes, or until they float to the surface. Remove with a slotted spoon and place on a plate lined with paper towels to drain excess water.
5. Serve
   Melt 4 tablespoons of butter in a large skillet over medium heat. Add boiled pierogi and pan-fry until golden on both sides, about 2-3 minutes per side. Serve immediately with additional sour cream and chopped fresh dill or chives if desired.