To mark the launch on April Fool's day, the burger giant released a hidden-camera-style promo video showing the serving of plant-based Whoppers instead of meat to customers who marvel that they cannot tell the difference.

"We wanted to make sure we had something that lived up to the expectations of the Whopper," said Burger King's North America president, Christopher Finazzo. "We've done sort of a blind taste test with our franchisees, with people in the office, with my partners on the executive team, and virtually nobody can tell the difference."

The Impossible Whopper comes at an extra cost - about a dollar more than the beef patty Whopper. But Finazzo said research shows consumers are willing to pay more for the plant-based burger.

Plant-based meat substitutes have been gaining popularity as more attention is focused on the environmental hazards of industrial ranching. Finazzo said his research shows customers mainly like it for the health benefits. The Impossible Burger patty has zero cholesterol.