Finally I found it!

When I was studying abroad the summer between my Junior and Senior years in high school, I went on this weird art installation tour (for like… 9 hours on a bus) around the Ruhrgebiet. It was really fascinating and I finally just found something that has a little information about it (randomly, while poking around a German food blog…).

Anyway, for posterity: http://www.route-industriekultur.de/menue/menue.html