Butter a 9X13 baking dish.
In a heavy pot melt the butter and whisk in the flour. Cook the roux for a few minutes over medium heat to cook off the raw flour taste.
Add the cream to the pot and whisk the roux into the cream until the sauce is smooth.
Add the cream cheese chunks and whisk until smooth.
Season this with garlic, nutmeg, Kosher salt and pepper.
Lay out a layer of potatoes, sprinkle them lightly with salt and pepper.
Ladle a thin layer of the sauce over the potatoes and sprinkle with Fontina and parmesan.
Add another layer of potatoes and repeat this process over and over until the potatoes are gone, ending with a layer of sauce and parmesan and a sprinkling of fresh chives.
Bake at 325 degrees for 1 hour or until the potatoes are tender and the top is golden brown.