The news comes weeks after the fast food chain first announced a pilot test in St. Louis.

On April 1, Burger King announced that it was testing Impossible (aka plant-based) Whoppers in the St. Louis area—with all the customary fixings you’d expect, like mayo, lettuce, tomatoes, and pickles, simply swapping a meatless patty in for the usual beef. The Impossible Whopper made its soft debut at 59 different Burger King restaurants, with the intention that if the tests went well, a national launch would be on the horizon. Today, Burger King confirmed those plans, announcing its goal to roll out the Impossible Whopper nationwide by the end of 2019.

Impossible Whopper
Credit: Courtesy of Impossible Foods.

“The Impossible Whopper test in St Louis went exceedingly well and as a result there are plans to extend testing into additional markets in the very near future,” Burger King said in a statement. “Burger King Restaurants in St Louis are showing encouraging results and Impossible Whopper sales are complementing traditional Whopper purchases.”

We previously had a chance to chat with Impossible's COO and CFO David Lee about the rollout, and he said that when he visited Burger King’s headquarters to try out the new burger, even employees couldn’t tell the difference between the Impossible Whopper and regular Whopper. “I literally remember getting the reaction from certain Burger King employees, the shock of ‘wow, wait, this isn’t made out of beef?’” Lee said. “So after seeing that and the excitement there at headquarters, I became very convinced that we had a great future partnership in the market.” With news of the partnership and launch, we have to wonder—when will McDonald's, one of the largest fast food chains in the world, debut a plant-based burger (we're looking at you, Big Mac) of its own?

Right now, the Impossible Whopper is still available in St. Louis area, in case you feel like hopping on a plane to try it; details about expansions and future testing sites haven’t been announced yet. In the meantime, however, we recently conducted a taste test on all the major players in the plant-based burger industry right now—including the Impossible 2.0 patty, with the addition of the Beyond Burger, Lightlife Plant-Based Burger, and Morningstar Farms Meat Lovers Vegan Burger, to see what meatless options consumers have ahead of grilling season. We found some burgers (almost) identical to beef; others had a more falafel-like flavor. You can find out which one was our ultimate favorite in the full article.