Bless you for serving real mashed potatoes, hopefully made with real butter, and real gravy. All sins of your misspent youth are forgiven. I’d love to visit your restaurant someday.
I m not surprised, if you are younger, that you never had sour cream raison pie. Since I first came to Iowa also to misspend part of my youth some 42 years ago, the dining scene has changed dramatically. You hardly used to see a chain. A few Pizza Huts, A&W s and the like, but that was about it. You could go anywhere in the state and find young people enjoying foods like homemade pies and outstanding pork tenders at mom and pop small cafes and drive ins.
Now, as you sadly know, young adults dine at chains, chains, and more chains. Oh, there may be an independent pizza hangout in a small city that the kids like and far more ethnic places than before, but with some exceptions like the Hamburg Inn in Iowa City, the small independent cafes that remain tend to serve an older crowd, as I guess you likely do. These are the places where you often find sour cream raison pie or whatever the people in an area choose to call it.