Wash and peel the potatoes. Place the potatoes into a sous vide bag with the salt. Vacuum seal on full pressure
Steam the potatoes at 90°C for 1 hour (this process is to set the starch of the potato allowing it to be easily cut and brown evenly). Leave until cool to touch
Use a thin sharp knife to cut deep incisions (¾ of the way) into the potatoes in 5mm increments
Insert 3 bay leaves into each potato
Melt the goose fat and baste the potatoes
Season with white pepper
Cook at 180°C for 1 hour, or until the potatoes are crisp and golden brown, basting frequently with fat from the pan