Gratin of potatoes with morels and yellow wine

For this delicious and very tasty morel mushroom and vin jaune gratin, we're staying in the spirit of the gratin Dauphinois, so no cheese, but with a double use of vin jaune: to sauté the morels, and in the cream that will be poured over the potatoes before cooking.

This is a full-flavored recipe, in which each ingredient is used to the full.