Pierogi (Polish Dumplings)

Begin by preparing the sauerkraut filling: melt 2 tablespoons of butter in a skillet over medium heat. Add the chopped onion (about ⅓ cup) and sauté until it turns translucent and releases its sweet aroma, approximately 5 minutes. Stir in the well-drained sauerkraut and continue cooking for another 5 minutes to meld the flavors. Season this mixture with salt and freshly ground pepper to taste, then transfer it onto a plate to cool completely. Next, prepare the mashed potato filling: in a separate skillet, melt 3 tablespoons of butter over medium heat. Add ½ cup of chopped onion and cook until soft and translucent, about 5 minutes. Gently fold these onions into 2 cups of creamy mashed potatoes, seasoning the mixture with salt and white pepper for a subtle heat and seasoning depth. To craft the dough, start by beating together 3 eggs and a pot of sour cream until the mixture is smooth and velvety. Sift 3 cups of flour, ¼ teaspoon salt, and 1 tablespoon baking powder into the sour cream blend, stirring until the dough forms. Knead this dough on a lightly floured surface until it becomes firm yet pliable and smooth. Divide the dough into two halves. Roll out one portion to about 1/8 inch thickness, then use a 3-inch biscuit cutter to cut out rounds. Place a modest spoonful of the mashed potato filling in the center of each dough round. Moisten the edges with water to seal the dough securely, fold it over into a half-moon shape, and press the edges together firmly using a fork, ensuring no filling escapes during cooking. Repeat the process with the remaining dough and the cooled sauerkraut filling. To cook, bring a large pot of lightly salted water to a rolling boil. Gently add the pierogi in batches, taking care not to overcrowd the pot. Boil for 3 to 5 minutes or until the pierogi float to the surface, signaling they are perfectly cooked. Use a slotted spoon to remove them carefully. For an extra touch, you can pan-fry the boiled pierogi in butter until golden and crispy before serving. Tip: Ensuring the filling is cool before assembling helps prevent the dough from becoming soggy. Also, make sure to seal the pierogi edges tightly to avoid any filling leakage during boiling.