Peel and cook the potatoes until soft.
Mash the potatoes (preferably with a potato ricer) and add to a large bowl.
Press the potatoes into an even layer and divide them with a knife into 4 equal parts. Take out one part of the potatoes out of the bowl. Add the potato starch in place of the removed potatoes. Add the removed potatoes back to the bowl along with soft butter. Please see the photos in the body of the post for reference!
Season with salt and pepper and knead a smooth dough.
Note: This is an old-fashioned way to make this recipe. You should have the same amount by volume of the potato starch as 1/4 of the potatoes that are taken out of the bowl. If you don't want to use this method, just measure out all the ingredients in grams and add them to the bowl.
Shape balls from the dough in the size of a walnut. Flatten each ball and place on a wooden board / baking sheet.
Using the end of a wooden spoon, make an indentation in the middle of each flattened ball.
In the meantime, bring a large pot of salted water to a boil, lower the heat to a gentle simmer.
Cook 8-10 kluski at a time, stir them with a wooden spoon after adding them to the pot to prevent them from sticking to the bottom.
When kluski float to the surface, cook them for 3 minutes then remove them from the pot with a slotted spoon. Repeat with the remaining kluski.
Enjoy!