Loren Lacy has spent nearly four decades comparing breaded pork tenderloin sandwiches from eateries across Iowa. So when he and his wife, Amy, bought a restaurant about a year and a half ago, they set out to make their sandwich better.

 Loren and Amy Lacy own PrairieMoon On Main in Prairieburg, home to the 2020 Iowa’s Best Breaded Pork Tenderloin sandwich. Their tenderloin became a top seller at PrairieMoon...