This route ascends the steep east face of Corteo. The scrambling is difficult in places and there is a lot of loose rock. It is shorter than the southwest ridge route, but is probably more exposed. It is difficult in the early season and can be quite dangerous.
Approximate route on the east face.
Follow the Maple Pass Trail to Maple Pass, where you will get your first view of Corteo. From here, drop 100' then traverse west towards Horsefly Pass. Continue traversing across the slope to reach the southeast ridge about 6900' at the base of the cliff band. Ascend the ridge as far as you can, then traverse across the face, aiming for the notch between the summits. When you see an opportunity, scramble up on ledges toward the summit.
I descended this route in the early season when there was still a lot of snow and it was very dangerous downclimbing. A slip on the steep snow would send you right over the cliffs. I traversed across the face to the big steep snow chute and was able to slide down it between the cliff band. It was so steep that even self arresting the whole way down I was still moving very fast. Fortunately it has a pretty good runout at the bottom so I wasn't too worried.
Looking down the steep east face.
Helmet; ice axe in early season. May want rope for descent.