Dishes Invented In Iowa Restaurants?

I'm trying to find every restaurant/hotel/eatery that invented or first served a specific regional dish in Iowa. So far I know of:

1.Taco Pizza- Happy Joe's

2.Steak De Burgo- Johnny & Kay's or/ Vic's Tally Ho

3.Tavern Sandwich- Ye Old Tavern (although loose meat sandwich may be from Montana originally)

4.Chocolate Ice Cream Bar- Royal Ice Cream Parlor

Know any others?