Nyon and Chamossière are the highest points and the best sectors for powder hounds. These are lift-accessed off-piste areas, a dedicated Freeride Zone between the two peaks.
Nyon has a multitude of lines down the face, and Chamoissière has a perfect un-pisted bowl to skiers' right. It does get tracked pretty quickly, but it's a big area so you should be able to score multiple laps before the snow loses any appeal.
If you're new to off-piste, the tree runs up the Super Morzine might be perfect. They are a great place to help perfect powder turns and if you're not looking to go too far from resort.
Off-piste skiing or snowboarding is different to piste skiing or snowboarding, and therefore needs a slightly different approach. It's definitely worth a lesson in 'off-piste' techniques if you're new to it, or would like some tips for riding steep and deep powder. It also pays to have someone with a bit of local knowledge, a mountain guide/off-piste instructor will be able to show you all the best spots to suit your ability.
For those of you that enjoy ski touring, Avoriaz has made the whole area ski tour friendly, and it's a great way to see a side of the mountains that you wouldn't ordinarily be able to.
Ski touring and avalanche gear can be hired from most ski shops. It’s recommended to go with a professional, and never to go off-piste on your own.