Pierogi

Prepare the dough: In a large bowl combine the flour, salt, sour cream, and eggs. Roll onto a lightly floured surface and knead for five to seven minutes, until smooth. Use additional flour for dusting the work surface. Cover the dough with a dampened tea towel or plastic wrap and let rest for 30 minutes at room temperature.

Prepare the filling: Peel the potatoes and cut into quarters. Add to a large stockpot with a teaspoon of salt and cover with cold water by two inches. Bring to a boil on high heat then reduce heat to simmer till tender, about 25 minutes.

While potatoes cook, finely chop the onions. In a large pan set on medium heat, melt the butter, add onions, and season with salt and pepper. Cook gently until onions are gold or amber, adjusting heat as necessary, taking care not to brown but to allow the natural sugars to carmelize from the inside, about 30 minutes, or more as necessary.

Drain cooked potatoes and transfer to a large bowl. Run potatoes through a potato ricer three times, starting with the largest disc and ending with the finest. In the large bowl with the riced potatoes, add onions and quark cheese. Season with salt and pepper, stir to combine. Set aside and let cool.

Divide dough into two pieces. Place one piece on a floured surface and leave the other under the dampened towel to stay moist. Dust work surface with flour and roll out the dough until it is ⅛ inch thick. Using the cutter, cut about 15 disks.

Assemble the pierogi: Have a cup of water handy. Place a little less than a tablespoon of filling the center of each disk. Using your finger and the cup of water, lightly wet the edge of one half of the disk. Pull the dry half over the filling and press against the wetted edge. Pinch the middle, then work up from the two sides, forming a seal. You can make a crimped pattern by pushing the rounded edge between your thumb and finger, working along the edge. Additionally, you can use a fork to pinch the seal. Place individually on a baking sheet lined with parchment.

Repeat with the remaining dough.

At this point, you can freeze the pierogies in one layer on the baking sheets. Once frozen you can put into a container or freezer bags to use at a later time.

To cook the pierogies bring a large pot of salted water to a boil. Cook in batches so they do not crowd the pot and stick to each other. The pierogies will float to the top in about two minutes. Continue to cook for another 3 minutes. Use a slotted spoon to transfer to a baking sheet lined with a rack to drain. Repeat with the remaining pierogies.

Serve as they are topped with some browned butter and sour cream or pan-fry them first in butter until golden.