Potato Pierogi

• Pierogi wrappers:
• 1 large egg yolk
• 1 c. whole milk
• 1 tbsp. vegetable oil
• 1/2 c. water
• 31/4 c. all-purpose flour
• Topping and filling:
• 4 tbsp. unsalted butter
• 5 c. finely chopped onion
• 4 c. leftover mashed potatoes
• 4 oz. farmer's cheese
• 2 tsp. salt
• 1 tsp. black pepper
• Assembly:
• 2 large egg whites
• 2 tbsp. water
• All-purpose flour as needed
• Sour cream or applesauce, for serving

1. 1. To make wrappers, combine egg yolk, milk, oil, and water in a small bowl. Place flour in a large bowl, pour in wet ingredients, and fold together to form dough.
2. 2. Transfer dough to a lightly floured board and knead for 3 minutes. If too sticky, add small amounts of flour. When dough is smooth, form into a ball, transfer to a small bowl, cover with plastic wrap, and refrigerate for 20 minutes.
3. 3. To make filling, melt butter in a large pan, add onions, and saute over medium heat, stirring occasionally, until browned, about 10 minutes.
4. 4. In a large bowl, combine 3/4 cup of cooked onions, potatoes, cheese, salt, and pepper. Set aside at room temperature. Reserve remaining onions for topping.
5. 5. In a small bowl, combine egg whites and water. Set aside for assembly.
6. 6. Remove dough from refrigerator and divide into three sections. Place one section on a well-floured work surface and roll out until very thin (about 1/16 inch). Cut circles of dough using a round cookie cutter (or a jar lid or juice glass).
7. 7. Place a heaping spoonful of the filling in the center of each circle, leaving a border. Brush some egg white mixture on half the outer border and fold dough over into a half-moon shape. Crimp edges with a fork.
8. 8. Transfer pierogi to a floured board or platter. Do not stack. Repeat with remaining dough and filling.
9. 9. Cook pierogi in batches for 4 minutes in a large stockpot of salted boiling water. Drain and transfer to a serving platter. Repeat with remaining pierogi, allowing water to return to a full boil each time.
10. 10. Serve with the reserved sauteed onion and oodles of sour cream or applesauce.
11. Try them fried: Cook in boiling water as above for 2 minutes rather than 4, then saute in butter until golden brown.

pierogi wrappers, egg yolk, milk, vegetable oil, water, allpurpose flour, topping and filling, unsalted butter, onion, leftover mashed potatoes, s cheese, salt, black pepper, egg whites, water, flour, sour cream

Taken from www.epicurious.com/recipes/member/views/potato-pierogi-50062434 (may not work)