In fast food news and trends, a defining feature of the past year has been the fried chicken sandwich wars. From Popeyes to McDonald's to Wendy's, it seems like every fast-food franchise has introduced its own chicken sandwich to great online fanfare and discussion, and lesser-known chain Wingstop has joined the fray.

On September 9, it had only been a week since Wingstop introduced its line of 12 chicken sandwiches, and by that date, all 12 varieties had sold out nationwide. According to QSR, the chain sold over one million chicken sandwiches in less than a week, eclipsing expected sales by 300%, but this was not achieved by mere luck.

Wingstop pushed an aggressive ad campaign for their sandwiches on social media, which included a "Chicken Sandwich Split" giveaway. However, several Twitter users have shared pictures of undercooked meat in their sandwiches; the chain has yet to respond to the issue, but hopefully it will be fixed when the sandwiches return.