When I was a kid, the fanciest restaurant my siblings and I could ever think of going to was Win Schuler's. After all, they actually had real tablecloths instead placemats! It also brought out the obligatory, "you better mind your manners if you ever want go out in public again" speech by my dad, while driving there in the car.
One of the things they were known for was their bar cheese. If I remember correctly it was served out of a small ceramic crock. It had a wonderful tangy flavor, thanks to a bit of horseradish. It was a treat we looked forward to. In latter years it became available in grocery stores.
After reading your post I checked for any copycat recipes online. I found a lot of them. Some looked like they came from rather authentic sources. I was shocked to find out that the first ingredient listed in most all of them was Velveeta cheese. Several also added a notation: Absolutely No Substitutions. The only recipe that had a different cheese listed, was one calling for cheese wiz.
I am not a fan of Velveeta, and cheese wiz would be even lower on my list. I guess there is probably a lesson in there somewhere. Perhaps it is about how things we like the least have the capability to be part of something we treasure. I am probably reading too much into it, but thanks for reviving a childhood memory.