# What You Need:
→ Dough
01 - 3 cups all-purpose flour
02 - 1 large egg
03 - 3/4 cup lukewarm water
04 - 2 tablespoons sour cream
05 - 1 teaspoon salt
06 - 2 tablespoons unsalted butter, melted
→ Filling
07 - 1 1/2 pounds russet potatoes, peeled and cubed
08 - 1 cup farmer's cheese or well-drained ricotta
09 - 1/2 cup sharp cheddar cheese, grated
10 - 2 tablespoons unsalted butter
11 - 1 small onion, finely chopped
12 - Salt and black pepper, to taste
→ To Serve
13 - 2 large onions, thinly sliced
14 - 3 tablespoons unsalted butter
15 - Sour cream, for serving
16 - Chives or parsley, chopped (optional)
# Step-by-Step:
01 - Combine flour and salt in a large bowl. Create a well in the center and add egg, melted butter, sour cream, and lukewarm water. Stir to combine, then knead on a floured surface for 5 to 7 minutes until smooth and elastic. Cover with a damp towel and let rest for 30 minutes.
02 - Boil cubed potatoes in salted water until tender, about 15 to 18 minutes. Drain and mash until smooth. In a skillet over medium heat, melt 2 tablespoons butter and sauté finely chopped onion until golden, approximately 5 minutes. Combine mashed potatoes, sautéed onion, farmer's cheese, and cheddar cheese. Season with salt and pepper to taste. Allow to cool.
03 - Roll out dough on a floured surface to 1/8 inch thickness. Cut out 3-inch diameter circles. Place 1 heaping teaspoon of filling in the center of each circle, fold in half, and pinch edges firmly to seal. Cover assembled pierogi with a towel to prevent drying.
04 - Bring a large pot of salted water to a gentle boil. Cook pierogi in batches; once they float to the surface, continue boiling for an additional 1 to 2 minutes. Remove with a slotted spoon.
05 - Melt 3 tablespoons butter in a large skillet over medium-low heat. Add thinly sliced onions and cook slowly, stirring frequently, until deeply golden and sweet, about 20 to 25 minutes.
06 - In the same skillet, fry boiled pierogi in batches, cooking 2 to 3 minutes per side until golden and crisp.
07 - Serve pierogi hot topped with caramelized onions, a dollop of sour cream, and chopped chives or parsley if desired.