This is a fabulous route in a peaceful valley.
From the parking at Plampinet head NNW on the GR 5/57; this is a ski de fond track that doesn’t follow the exact route and twist and turns, so follow it but cut corners where possible. At 1582m turn west on a track leading through the trees, follow this to the Torrent Creuzt. It briefly comes back on the ski de fond track, and then head south into that valley.
There are 2 choices as the valley steepens : stay in the valley floor and head up through a tight gully or cut left and gain height on a more open slope - there isn’t a lot of difference time wise. As you get into the higher part of the valley and out of the trees you will see the north couloir very clearly. Head up and follow it as it bends left. The couloir doesn’t lead to the summit; it is possible but involves descending the other side and climbing a different ridge.
Follow the couloir back down and at the bottom traverse into the valley bottom through the trees and the tight gully seen on the way up. Continue on easier angle terrain though trees back to the ski de fond track. Here you have a choice - cut back through the trees you came up (this route can be tight in places and tricky in poor snow) or stay on the ski de fond track. If you stay on the ski de fond track it goes in loop and you will have to skate or pole up small hill sections. Either way brings you back on the GR5/57 and back to Plampinet.
Note – this route goes over two maps with no overlap –3535OT and 3536 OT - but there's no such worries with our map!