The plant-based "All Whopper. No beef," patty is said to dupe even the most diehard beef fans, and it's been years in the making. The startup behind it, Impossible Foods, has helped restaurants like White Castle, Red Robin and Hard Rock Cafe add imitation meat products to their menus. According to Reuters, celebrities including Jay-Z, Will.i.am, Jaden Smith, Katy Perry, Serena Williams, Kirk Cousins and Paul George have invested in the company, and Bill Gates, Google Ventures, Horizons Ventures and UBS have committed support. Impossible Foods raised more than $300 million in its latest round of funding, and it could be headed for an initial public offering.

Proponents hope it can be an environmentally-friendly alternative to classic beef patties, and in Burger King's case, there's some indication that it's attracting customers who wouldn't normally eat at the chain. But it still has to taste good. As Impossible Foods' CFO told Reuters, "It's the craveability that makes meat eaters find their own reason to come back for Impossible Burger."

The Impossible Whopper tour bus will stop in Miami on Thursday, before making its way to Columbus and Montgomery. You can track the tour locations on Burger King's Facebook page. If you can't make it to one of the four cities that now sell Impossible Whoppers, you shouldn't have to wait too long until Burger King launches the patties nationwide.