Authentic Polish Pierogi with Potatoes and Cheese (Pierogi Ruskie)

Pole here with Ukrainian wife. Actually it’s a traditional Ukrainian dish.
Ruskie has nothing to do with Russia, it’s how the land was named in the past (ruś).
Russia actually took the name for themselves as a part of the assimilation tactic. That’s when Ukrainians started calling themselves Ukrainians to differentiate themselves.

Say to my wife that pierogi are polish dish or have anything to do with Russia and she will rip your head off