Other traditional fillings include mashed potato, cottage cheese and herbs, so feel free to try different options.
2 cups plain flour, plus extra for dusting
½ teaspoon baking powder
¾ teaspoon table salt
½ cup warm water
1½ teaspoons neutral oil
1 large egg, size 7
1 tablespoon extra virgin olive oil
2 large brown onions, thinly sliced
½ cup sauerkraut, drained and roughly chopped
1 clove garlic, thinly sliced
sea salt and ground pepper
10 brown mushrooms, thinly sliced
75 grams salted butter
1 cup sour cream or plain yoghurt
handful parsley, finely chopped
1 teaspoon ground paprika
Dough: Sift the flour, baking powder and salt into a large bowl. Make a well in the centre of the dry ingredients and pour in the water, oil and egg. Use a fork to bring the ingredients together to make a soft dough. You may need to add 2-3 teaspoons more water if the dough is too dry. Use your hands to knead the dough in the bowl for 2-3 minutes, then cover with a tea towel and leave to rest for 30 minutes.
Filling: Heat the olive oil in a large sauté pan over a medium heat. Add the onions and sauerkraut and cook, stirring occasionally, for about 8 minutes until the onions begin to brown. Add the garlic and season generously with salt and pepper. Cook for a further 4 minutes. At this point, remove half of the fried onion mixture and set aside in a bowl – these will be used to serve. Add the mushrooms to the pan and fry for a further 10 minutes. Remove from the heat and set aside to cool.
Fill a large saucepan with salted water and bring to the boil.
To assemble: Divide the dough into 4 pieces. On a well-floured bench, roll each piece out to about 3mm thick. Dust the top of the dough with flour. It’s important to keep the dough well-floured to avoid sticking and tearing. Using a round cookie cutter or glass (approximately 5cm diameter) to cut circles out of the dough, cutting the circles as close together as possible. Place on a lightly floured tray with clingfilm between the layers to stop them sticking together. You should get at least 40.
Fill each circle of dough with approximately 1 teaspoon of the filling. Brush a small amount of water around the edge, then fold them over and seal tightly by pressing with a fork. It’s important to completely seal the dumplings to avoid them filling with water when boiling.
Working in batches, drop the pierogi into the boiling water and cook for 3 minutes. Remove with a slotted spoon and place on a large plate until all the pierogi are cooked.
To serve: Reheat the reserved fried onions in a large sauté pan and add the butter. When hot, add the pierogi and cook for 2 minutes until gently warmed through and coated in the buttery onions. Divide among serving plates. Top with the onions, a dollop of sour cream or yoghurt, the parsley and a pinch of paprika..