The fast-food restaurant chain added a vegan Whopper to its menu at the start of this month. The burger was created in collaboration with startup company Impossible Foods, which makes its Impossible Burger out of wheat and potato protein, coconut oil, heme, and some binders. Source 1b
Burger King's Impossible Burger (Hover)
So Burger King decided to add a vegan option which is purely for sales as they will still be selling dead cows and chickens next to it. Anyway, is this something you will go for? I guess it will appeal to taste rather than health.
Besides what the good doctor said, it is important to note that the Impossible Burger is not vegan because they cook the patty in the same place they cook the other meats, at least they do it that way locally. Now Burger King will say that the grill is self cleaning so it is cleaned before using the plant based burger but for vegans that won't do because of the connection with dead animals being cooked in the same place.
In my humble opinion maybe it is vegetable meat cooked in some way that makes it look like real meat to physically but it depends. If we somehow get a chance to get to where they reproduce the meat then we might as well get answers or even more questions. Vegetables and other plant based food tend to quickly and easily lose their flavor and nutrients when cooked for long periods of time so it might be really meat from within.