I fly out of the Charlotte Douglas Airport every single weekend for work and I always stop by Red Mango for their Chicken Apple Pesto Flatbread and sometimes a berry banana smoothie (I prefer their smoothies to Jamba Juice and they have more options in my opinion)
The Flatbread is the most delicious combination of savory, sweet, and cheesy and I literally crave it all the time. I have never been disappointed and their service is so quick! I would definitely recommend them for a quick grab meal during a layover!