1.5 c heavy cream
1.5 c Chicken stock
5 cloves garlic, smashed with side of a knife
1-2 Sprigs Rosemary
2 tsp Kosher salt
2 tsp fresh ground black pepper
6 Idaho russet potatoes
2 tbsp unsalted butter
.75-1 c Grated Gruyere
.5 tsp Grated nutmeg
Preheat oven to 400 degrees Fahrenheit.
Rub one clove of garlic split in half all over a 10-by-14-inch gratin dish. Let rest for 10 minutes. Butter gratin dish and place aside.
Combine stock, heavy cream, garlic, rosemary, nutmeg, salt and pepper in a medium saucepan.
Bring to a medium simmer, lower heat and continue to simmer for 30-45 minutes. Cook until thick and slightly reduced.
Strain out garlic cloves and rosemary.
Peel potatoes and cut into 1/8-inch slices.
Arrange first layer of potatoes in the butttered pan, overlapping the potatoes a bit.
Sprinkle the potatoes with .5 cup of the liquid and 2 tablespoons of the grated cheese.
Repeat with remaining potatoes and cream, about 4 layers.
Add the remaining cheese after the final layer of potatoes.
Cover with aluminum foil and bake for 45 minutes. Remove foil and bake another 30 minutes, until top turns golden brown.
Remove from oven, let rest for 10 minutes before serving.