Shake Shack announced last week that it is adding chili to its menu. Customers can order the new chili-based items from the chain's app starting Monday. For a limited time, the chain will serve chili cheeseburgers, chili cheese dogs, and chili cheese fries at locations across the US. The chili is made with slow-braised beef, as well as ancho and chile de arbol peppers. Shake Shack is debuting the chili menu items on Thursday, however, customers can order them on Monday using the app.