Wingstop Inc. /zigman2/quotes/206814832/composite WING +3.37% announced the addition of thighs to the chicken chain's menu following the successful launch of its virtual brand Thighstop. Available on DoorDash Inc. /zigman2/quotes/222973991/composite DASH -1.32% , Thighstop was launched this summer during a shortage of chicken wings. Thighstop will continue to be available on the delivery platform. Now bone-in thighs and boneless Thigh Bites will also be available on the company's main menu. And Wingstop is launching "Thigh Thursday," which offers deals on that day of the week. Virtual brands, like Cosmic Wings launched by Applebee's parent Dine Brands Inc. /zigman2/quotes/205160666/composite DIN -2.08% , have taken off across the restaurant category. Wingstop stock has rallied 33% for the year to date while the S&P 500 index /zigman2/quotes/210599714/realtime SPX -0.16% has gained 20.1% for the period.