I think most Nebraskans would tell you that there are a few restaurants in Lincoln that are "must-eat-at" places whenever one visits. There are 4 to come to mind (in no particular order)
Taco Inn, Runza and Amigos are all fast food restaurants and Valentino's is a pizza joint. My "must-eat-at" places are Taco Inn and Runza, so we made sure to visit each while I was there.
A runza is a German food. It has seasoned ground beef, onions and cheese, wrapped up in dough and baked. It's so delicious. They also have really good fries.
Taco Inn is definitely my favorite. I worked there for 3 years during high school and still love it. They have the best tacos, burritos and nachos. This is the food we took when we ate lunch with M at her school. I had two tacos and a deluxe burrito.