Start low in the cave and move up and out with your best heelhooking, pinching, and core tension techniques. Slap for a good spot on the lip and then prepare to mantle and creep up the slab to the top.
Also try the much harder Thunderdome variation that continues out right.
Location
Straight uphill from the Yosemite Highball boulder. Look for the huge black charred tree that is 10ft. from the problem.
I have heard people say this feels burly now: Ben, Jesse and I were out there last fall and broke both the left hand thumb catch near the lip and a nice foot for rocking over onto the slab. It definitely felt harder after that. Sorry!