Preheat your smoker or pellet grill to 275°F. Poke a few holes in each potato and place the peeled potatoes into the smoker.
Let smoke until they are easily pierced with a wooden skewer.
Remove from the grill and mash with the heavy cream and sour cream.
Put the potatoes into a grill-safe baking dish. Place dollops of the Boursin cheese and butter over the top of the potatoes and place back into the grill. Increase the heat to 325°F.