Potato and Cheese Pierogi Recipe

Ingredients (16)

• For the Filling:
• 5 tablespoons (75g) unsalted butter, divided
• 1 large onion (10 ounces; 285g), finely chopped
• Kosher salt and freshly ground back pepper
• 1 pound (455g) russet potatoes, peeled and cut into 1-inch pieces
• 6 ounces (170g) farmer cheese
• For the Dough:
• 12.5 ounces (about 2 1/2 cups; 355g) high-protein all-purpose flour, such as King Arthur (see note)
• 1 teaspoon (4g) Diamond Crystal kosher salt; for table salt use half as much by volume or an equal amount by weight
• 8 ounces (1 cup; 225g) sour cream
• 1 large egg
• To Assemble and Finish:
• 2 tablespoons (30ml) vegetable oil, divided
• 2 tablespoons (30g) unsalted butter, divided
• Sour cream, for serving
• Sliced chives, for serving (optional)