From the inside of the Amphitheatre, there is an obvious roof and slot on the wall below the West Bench.
Climb up to the slot, get into it, and grunt your way up a few moves until you can exit onto the face. Climb the face more or less straight up to a steep final headwall. Climb the obvious crux finger crack for a few moves to the West Bench.
Rossiter calls this route, Slot.
Per Sam W: for those sensitive, there are wasps on this route.