According to Chad Greedy, Adam Ondra has made the first ever flash ascent of Daniel Woods' Jade, ~8B+, in the Upper Chaos Canyon, RMNP, Colorado.
Watch The Video (press play then maximise the video):
Originally 8C was suggested for the problem, but it has now since long settled at 8B+.
This grade has been flashed before by Woods (Entlinge, Murgtal) and by Adam himself twice (Confessions, Cresciano and Gecko assis, Fontainebleau).
Still, I would say this is probably the hardest flash ever.