The savoury or sweet boiled dumplings called 'pierogi' are a speciality of which country?

I learned that quark is a type of cheese (something like cottage cheese but a sour cream flavor). It is not always a subatomic particle.

Nada, my great grandma made the best ones, she was Slovak.

It's wrong! Pirogi likely originated somewhere in Central Europe or Eastern Europe, and has been consumed in these regions, not only Poland.