To Make the Dough

1. On a clean work surface, place all of the 7½ cups of flour into a pile. Stir in salt then make a valley in the center of the flour. Crack both eggs into center along with sour cream. With a fork, start stirring the eggs and sour cream into the flour pulling the edges toward the center. Then gradually add the water a little at a time as you continue to stir with a fork. You may not use all of the water so after 2 cups check texture and slowly incorporate another half cup of water. (Our dough was a perfect consistency at 2½ cups and we did not use the remaining ½ cup.) The texture should be soft and sticky to the touch.
2. (A scraper like this is helpful for this next step so you can scrape and mold the dough as it is floured and rolled.) Sprinkle flour over the top of the dough ball and surrounding counter and with the scraper (or a flat spatula if you don’t have one), scrape dough from counter over onto floured surface and continue this process adding flour as needed until you have a soft, pliable easy-to-handle dough that does not stick to the rolling pin.
3. Using a rolling pin, roll the dough mass out to 1/16th inch thin. If you roll it out any thicker, your yield will be less than 100.
4. As you roll, keep flouring the counter under the dough so when it is completely rolled out, none of the dough mass sticks to your counter.
5. Using a 3 inch round cookie or biscuit cutter, dip the cutter in flour if needed then cut out the circles as close to each other as possible. After filling this batch, gather up the scraps and roll back out and cut more circles. Finally roll up the last of the scraps and cut one last time. The dough is soft enough to get rolled out three times but no more. Also try to keep the dough covered with a slightly damp cloth to keep the dough from drying out.
6. The final count should be approximately 100 circles. See last step for filling, boiling and frying.

To Make the Potato Filling

1. Boil potatoes in salted water for 5-10 minutes until tender, then drain and place back into the pan. Heat over medium just long enough to evaporate any liquid left in the pan and to dry out the potatoes. Remove to a bowl and set aside.
2. In the same pan, melt butter over medium heat and add onion, salt and pepper and cook 3-5 minutes until tender. Remove from heat and add parsley and potatoes and using a potato masher, mash mixture to somewhat fine. Stir in cheddar cheese and set mixture aside. If not filling right away, refrigerate until needed.

To Make Sauerkraut Filling

1. In a medium sauté pan, melt butter over medium heat and add mushroom and onion and cook for 3-5 minutes until tender. Add drained sauerkraut, salt and pepper. Stir and remove from heat. If not filling right away, refrigerate until needed.

To Make the Cheese Filling

1. In a medium sauté pan over medium heat, melt butter and add onions. Cook 3-5 minutes and remove from heat. Stir in Farmer’s cheese and mix to combine. Stir in egg, parsley, salt and pepper and stir again. If not filling right away, refrigerate until needed.

To Make the Prune filling

1. Note: This is more of a dessert filling and can be served a few different ways. But the traditional way is, once cooked, serve with buttered and toasted plain bread crumbs.
2. In a small sauce pan place dried prunes and water just to cover tops. Add sugar and lemon and bring to a boil. Lower to a simmer and cook two minutes. Remove from heat and let the prunes sit in the hot water for ten minutes. Drain liquid and discard. Place cooked prunes in a blender or small food processor (like this one) and puree until smooth. If not filling right away, refrigerate until needed. Brown the ¼ cup of bread crumbs in the one tablespoon of butter over medium heat until slightly browned, about 4-5 minutes. Set aside for serving.

To Fill, Prepare and Cook the Pierogi

1. Each pierogi gets filled and cooked the same. As noted above, the prune pierogi are served with toasted bread crumbs as a dessert and the other three fillings served with grilled onions and sour cream as an entrée or side dish.
2. To fill each pierogi, follow the recipe for the filling and divide the filling between that number of circles.
3. 
4. Place the filling (between ¾ and 1 ounce depending on the filling type) in the center spreading it out into the shape of an oval. Have a small cup of water close by and with a pastry brush, lightly wet the outside of the circle half way around. Then lift the dough circle in your hand and pull the edge of the dry side to the edge of the wet side together in the center and pinch tight. Then work from the center out and pinch the rest closed, poking any filling back in as you go. Set the finished pierogi on a parchment-lined sheet pan.
5. Place a medium to large pot of water on to boil as you finish the remaining pierogi. Have a large sauté pan on a burner with the melted butter on medium low.
6. Once you have made as many as you plan on making, place about ten at a time into the boiling water (checking to make sure that they haven’t stuck to the bottom of the pot) and boil until they float (about 2-3 minutes). Then cook for an additional minute and remove with a strainer. Immediately add to pan with melted butter. All you are doing with this step is coating them in butter so they don’t stick to each other. Toss in the pan of butter for about 30 seconds and remove to a platter. Repeat for all of the pierogi you intend to cook.
7. In a large skillet over medium high heat, melt butter and add onions and cook for about 4-5 minutes until slightly browned. Remove to a bowl and set aside.
8. Using the same pan over medium heat, melt butter and add cooked pierogi. Cook flipping occasionally until browned on both sides, about 5-8 minutes.
9. Serve savory pierogi with sour cream and sautéed onions. Serve prune pierogi with buttered, toasted bread crumbs.