Pre heat the oven to 350 degrees. Spray a 9 x 13 inch casserole dish with cooking spray and set aside.
In a large pot, boil the potatoes in their skins until fork tender. Drain potatoes and rinse in cold water.
When cool enough to handle, peel potatoes and dice into ½ inch size pieces. Set aside.
In the same pot, heat the 4 Tbsp. butter over medium heat.
Add the flour and stir with a whisk. Slowly pour in the cream, whisking to dissolve the flour and butter mixture into the cream.
Add the salt, nutmeg and pepper. Cook over medium heat until the mixture is slightly thickened - about 3 - 5 minutes.
Add the potatoes and stir gently to coat with the cream mixture. Stir in the green onions.
Pour potatoes into the prepared casserole dish.
Bake uncovered at 350 degrees for 20 - 25 minutes or until the potatoes are lightly browned on the top and heated through.
Why use White Rose potatoes? Because you need a firm, waxy style potato. If you can't find White Rose, you could use Yukon Gold's - jus don't use Russets!Freshly ground pepper is crucial to this recipe - already ground doesn't have the same fragrance or potency. The potatoes can be completely assembled 1 day before cooking and refrigerated.