For what it is worth, some of our relatives were raving about potato pancakes from Trader Joe's. We did not have any of the pancakes at our meal -- folks were just talking fondly of them in the abstract -- so I can't say personally how good TJ's potato pancakes are but boy, everyone liked them. They are on my shopping list.
Alternatively, the Red Apple restaurant on Milwaukee Ave. has a giant buffet with dozens of food items but they will give you a styrofoam clamshell carry-out container and you can take just the excellent homemade potato pancakes and pay for them by the pound. The little old Polish ladies in the kitchen that are cooking them fresh all day long will thank you!

(Just TRY to get in and out of there without sampling the rest of the buffet! ha!)
Red Apple "Czerwone Jabluszko"
Address: 6474 N Milwaukee Ave, Chicago, IL 60631
Phone:(773) 763-3407
Prices:$$$$
Hours:
Saturday 11:00 am – 9:30 pm - See all
Monday 11:00 am – 9:00 pm
Tuesday 11:00 am – 9:00 pm
Wednesday 11:00 am – 9:00 pm
Thursday 11:00 am – 9:00 pm
Friday 11:00 am – 9:30 pm
Saturday 11:00 am – 9:30 pm
Sunday 11:00 am – 9:00 pm