Elsbeth, are you back from your trip yet? How about a progress report?
For another Iowa suggestion, stop at the Maid-rite place at the Avoca exit (Mile 40). When I was growing up years ago in Iowa, homemade loose meat sandwiches were an authentic Iowa tradition & Maid-rite epitomized this tradition. However, the entire Maid-rite chain in recent years seemed to have gone somewhat downhill.
Imagine my surprise today when I filled my gas tank at the I-40 exit & saw the skin-on homemade fries behind the Maid-rite counter. I quizzed the manager about her product. She said that the maid-rite meat used to come to the store already cooked but she stopped that & all of the meat is now cooked & seasoned on-premises. After hearing this, I gleefully order the Mega-rite (double portion of meat) & fries. I was transported back to my childhood.