Several years ago my husband and I became two of the many travelers through Tennessee who stop overnight in Cookeville (roughly halfway between Knoxville and Nashville). There are at least two dozen well-known chain restaurants there, but I would like to put in a good word for two locals.
The first is the Gondola Restaurant and Pizzaria. It's right off I-95 on Jefferson Ave across from the Baymont Suites. They serve Italian & Greek dishes, pizza and a nice selection of sandwiches, etc. What stands out here is the quality of ingredients. I can't remember another inexpensive restaurant which takes so much pride in what it serves, from shrimp in the seafood pasta to the pickle on the side of a patty melt.
The second was a wonderful surprise to my husband, a Thai food fan. It's Royal House Thai Cuisine. We live in NC and have tried many Thai places here. The Royal House comes up to the standards we expect in every way. If you've been driving along thinking "Better stick to BBQ in this town", not so if you like Thai. And don't let the S Willow Ave address deter you. It's very easy to find.