Yum! Brands (YUM - Get Report) owned KFC has been the rare standout in the sluggish fast food space of late, but there is more behind the brand's surprisingly strong performance than endless catchy TV commercials of founder Colonel Sanders. 

"The reality is that our operations have never been stronger, our taste scores and overall satisfaction scores are at the highest levels they have been in a long, long time," KFC U.S. president and Chief Concept Officer Kevin Hochman told TheStreet in an interview. Hochman explained KFC has spent 100,000 hours re-training store cooks and other employees in the "Colonel's values", such as how to better use the pressure fryer to make juicier chicken. 

Says Hochman, "A lot of people think they can get the secret recipe and they can make KFC, but that is not true."

Whatever the case, the combination of KFC's re-training efforts and new food launches such as the spicy Zinger sandwich and sweet/tangy George Gold are paying off. 

KFC's fourth quarter same-store sales in the U.S. rose 4%, marking the tenth straight quarter of gains. By comparison, McDonald's (MCD - Get Report) U.S. saw its same-store sales drop 1.3% during the fourth quarter, while Restaurant Brands International's (QSR - Get Report) Burger King notched a 1.8% increase.