These Polish dumplings are fun to make with the whole family and are filled with delicious mashed potato and cheese.
Sift the flour and salt into a large bowl.
Melt the butter. In a separate bowl, whisk together the melted butter, sour cream, egg and vegetable oil.
Add the wet ingredients to the dry ingredients, and stir with a wooden spoon until well blended. You can also use your hands. Cover and leave to rest for 15 minutes.
Meanwhile, peel, wash and chop the potatoes into small cubes. Boil the potatoes in salted water for 15 minutes.
Finely chop the onion and grate the cheese. Set aside.
Drain the potatoes and add back to the pan. Add the onion, grated cheese, cream cheese, salt, and pepper. Mash until smooth and set aside to cool.
Roll the dough onto a floured surface to a thickness of about ¼ cm.
Cut the dough with a pastry cutter, 5 cm in diameter.
Brush the outside edge of the dough with a little water and add a spoonful of the filling to the centre. Fold the dough over, forming half circles, pressing the edges to seal. You can seal the pierogis with a fork. Repeat with the remaining dough and filling.
Add the pierogis to a pot of boiling salted water. Cook for 5 minutes. They are cooked when they float to the top.
Serve the boiled pierogis with melted butter, or sauté the pierogis in a pan to create a crispy exterior, and serve with sour cream.