Burger King’s ‘Impossible’ Whopper Has No Beef Burger King has no Burger in their burger and Clara Peller is asking "Where's the Beef"? From her grave! Impossible Whopper — a vegetarian version of their flagship sandwich at outlets nationwide by the end of the year. The new veg-friendly option uses a patty from Impossible Foods, a California-based startup that develops plant-based alternatives for meat. Despite the switcheroo and new green paper wrapper, Burger King wants consumers to know that the sandwich is still 100 percent Whopper, despite the lack of beef.