There’s a little corner of sandwich heaven hiding in plain sight in Lisle, Illinois, where Schmaltz Delicatessen has been quietly perfecting the art of the Reuben while flashier eateries come and go.

So yes, people drive from all over Illinois to eat at this hole-in-the-wall restaurant in Lisle. And after your first visit, you’ll understand exactly why you should join them. For hours, special ...