You have to give B&B grocery/deli a try if you're in Des Moines, Iowa. This place has been around forever. They have absolutely fantastic breaded pork tenderloin sandwiches. IMO, they're the best in Des Moines.
In fact, they were named for having the best deli sandwich in Des Moines by the local newspaper. The food is great, the place is nostalgic, and the staff will make you feel like a regular. Even their menu on their web-site is cool... www.killerdeli.com
There's other deli's in Des Moines, but this one keeps me coming back for more.
B & B Grocery Meat & Deli
2001 SE 6th St, Des Moines, IA 50315