Your side dish was probably fried/sautéed onion and boczek - a type of streaky bacon, only unlike the streaky bacon in UK or Ireland, which is sold sliced and raw, or only very slightly smoked, Polish boczek is smoked as a whole piece of meat to the point you can eat it without additional cooking. Some people slice it and have it on bread, although we do dice and fry it to be served on top of pierogi or e.g. with scrambled eggs. Pierogi are always served with fried/sautéed onion on top and sometimes boczek. Depends on the household/restaurant guess. The pierogarnia you ordered from probably sends them separately, in case someone doesn't like onion. I've never heard of sauerkraut being a side dish for pierogi, although this may be a regional variance. However, sauerkraut is a popular side dish for let's say kotlet schabowy (pork schnitzel) or any meat+potatoes type dinner.

positive man, i like it:)

Greetings from Gdańsk! You suppose to cover Pierogi with that onions :) Sauer kraut is as side dish

Perła, it was only local in my univercity days so ppl from Lublin was taking like hunderts of bottles to the dorms and sell them to us. It became popular and lost some taste over the years as mas production went on but still I think its one of the best Polish beers.. The one you drunk, "Export" isn't the best. "Chmielowa" is their first and the best lagger.

You'd rather ask "which pierogi was your worst". I can say without hesitation - no one! All the rest depends of mood.

I'm not a fan of Polish dumplings with meat(pierogi z mięsem). I like Kołduny Litewskie - Lithuanian dumplings. Don't let the name confuse you. Once upon a time, Lithuania, western Belarus and Ukraine were part of Poland. Hence such names. Polish dumplings with meat are prepared from boiled meat. Kołduny are small dumplings stuffed with raw meat. Therefore, when cooked, they are juicy like Georgian khinkali. The iconic dumplings are Ruthenian dumplings. Sometimes incorrectly translated as Russian dumplings. The stuffing is cheese, potatoes and fried onion.

Dude you're supposed to mix the onions with the pierogi man, seriously. Mix it up then eat it together!

It's called dumplings mate......