A 5.7 route of this length and consistent quality is rare. Kor's Flake is hard, sustained, and exposed for the grade.
Hike up west past the large overhang of Turnkorner Buttress to a point shortly beyond the deep chimney separating it from the Guillotine Wall. Scramble up onto an outcrop below a deep, narrow chimney with some loose rock and a large chockstone about 30 feet up.
P1 - squeeze up the chimney, go right under the chockstone, and emerge to climb moderate rock for about 50 feet to a belay ledge. The namesake flake, a massive, left-angling 150 foot high exfoliation forming a long, right-facing, left-leaning corner, is visible up on the left.
P2 - climb the corner above the belay to gain the namesake flake, and go up it about 30 feet to an awkward belay (5.7).
P3 - finish off the flake, which turns into a wide crack/chimney, go over a small roof, and belay on a slab, about 150 feet.
2017 Edit: there are two ways to climb this pitch, both of which I've done on lead. If you stay out of the crack, it's 5.8 R (possibly R/X) stemming with *occasional* gear in incipient cracks. If you squeeze into the crack, it's a tight grunt but much more secure. Either way, bringing gear larger than a #4 Camalot is up to your discretion based on your honest assessment of your abilities on chimneys and/or 5.8 R face climbing. (Sorry if I sandbagged anyone pre-2017. When I first climbed this around 1999 or 2000, there was no mountainproject, the existing guidebooks did not recommend anything larger than 4", and I think it was probably rare to bring bigger gear on the route, but I could be wrong.)
P4 - climb up and left into a right-facing corner, but traverse left out of it after about 20 feet. Climb a continuous hand and finger crack to a good belay below a dihedral/roof (5.7, 130 feet).
P5 - climb around the overhang to the left (5.7), and stretch the rope out to easier ground. Finish up and right to find the descent gully.
Standard rack to a #4 Camalot or larger depending on comfort level on the chimney pitch. If unsure, the comments below contain more gear beta than you can shake a nut tool at :)