Harmony Hall is the best place to eat during your visit to Carowinds. You'll be delightfully surprised by the quality of food. It isn't your average theme park food, that's for sure.
I'd highly recommend any of the BBQ items. They smoke everything in house and it's pretty great.
Prices are in line with any entertainment venue. If you're looking to save money on any food during your visit, consider getting one of Carowinds' meal deals. It can save you big if you plan on visiting and/or eating more than once.