The chain's meatless patty, which was originally trialed in St. Louis, has since been rolled out in Miami, Montgomery, Alabama, and Columbus, and in the San Fransisco Bay Area.
'It's attracting new guests'
In response to the success of the trial, a spokesperson for Burger King said: "As a result, there are plans to extend testing into additional markets in the very near future."
The Impossible Whopper appears to be attracting new customers, with José Cil, the CEO of Burger King parent company Restaurant Brands International, said: "We aren't seeing guests swap the original Whopper for the Impossible Whopper...it's attracting new guests."
Impossible Foods controversy
Impossible Foods and its flagship patty have not been free of controversy; in 2017, it was revealed that a key ingredient - soy leghemoglobin aka 'heme' - from the brand's flagship item the Impossible Burger was fed to rats in order to test its safety. In excess of 180 rats were killed as a result of the testing.
CEO Pat Brown has reacted to the controversy, publishing a statement titled The Agonizing Dilemma of Animal Testing.