Try Schooners in Bloomington Illinois. The tenderloin is bigger than the plate it is on. It is Fantastic.
I have been living in Michigan and no one seems to know what a breaded tenderloin sandwich is. I have been searching for a drive-in, or any place, that serves one for a long time, but it seems they have all become part of the past.
I would love to have one right now, with a big rootbeer and onion rings. Yum Yum!