Rustic Double Cheesy Potatoes

Submitted by:  June Shockley
I saw this on the Food Network Show - Farmhouse Rules.  I have been making it ever since.  It is one of my favorites and I am sure it will be one of yours too!  If you add some diced ham it becomes a wonderful maindish.

Rustic Double Cheesy Potatoes

Ingredients
6 tablespoons unsalted butter
1/3 cup all-purpose flour
1 quart milk
3 cups shredded sharp Cheddar cheese Use good Cheddar not that orange stuff)
3 cups shredded Gruyere cheese
2 cloves garlic, smashed
1/2 teaspoon freshly ground pepper
Kosher salt
1/2 teaspoon freshly grated nutmeg
7 medium Yukon gold potatoes, unpeeled, cut in 1/2-inch thick coins
1/4 cup chopped fresh parsley, for garnish

Directions
Preheat the oven to 300 degrees F.

Melt 4 tablespoons of the butter in a large, oven-safe high-sided skillet over medium-high heat. When the foam subsides, add the flour and cook, stirring constantly, until it has the consistency of wet sand, about 3 minutes. Remove from the heat and whisk in the milk, little by little.

Put the saucepan over high heat and bring to a boil, whisking constantly. Lower the heat and whisk in 2 cups of the Cheddar, 2 cups of the Gruyere, the garlic, pepper and salt. Whisk until the cheese is melted, then stir in the nutmeg. Add the sliced potatoes to the pan. Scatter the remaining 2 tablespoons butter and the remaining 1 cup Cheddar and 1 cup Gruyere over the top