The best Polish deli ( for me) is Kasia's at approx. 2200 W. Chicago Ave. The are other good deli's on Western near Chicago Ave. I also like Rich's Deli on the corner of Iowa and Western.
As I stated in a past post, fo rmy money, Anjez's grill at approx. 1046 N. Western Ave. is a Polish culinary treasure. The best homemade periogis in Chicago! and has many other great dishes.
Enjoy, after eating there let me know how your experience was.