I make them for Christmas Eve with enough to have throughout the year. On Christmas Eve, they are part of the entire meal. We boil them and serve them with butter and onions with sour cream.
During the year, they can be a side, made the same way, or as a meal.
I can't wait to go to Poland when all this craziness ends to taste them in the motherland. When we had them in Russia, they were baked like a calzone, though stuffed with potato and cheese, cabbage and cheese, etc., like a pierogi that we'd have in this country. They were just larger and baked. The pierogies that they boil in Russia are stuffed with fruit filling and served in a sweet sauce. They were quite good.