3 pounds Yukon Gold potatoes, peeled and sliced into 1/8 inch rounds
4 tablespoons unsalted butter
1/4 cup all purpose flour
2 cups whole milk
1 cup heavy cream
3 cloves garlic, minced
1 teaspoon salt
1/2 teaspoon ground black pepper
1 teaspoon fresh thyme leaves
1/2 cup shredded parmesan cheese
1/4 teaspoon ground nutmeg
Instructions
Preheat your oven to 375 degrees Fahrenheit. Lightly grease a 9 by 13 inch baking dish with butter or a small amount of oil to prevent the potatoes from sticking to the sides during the long roasting process.
In a medium saucepan over medium heat, melt the butter. Whisk in the flour and cook for about one minute to remove the raw flour taste. Slowly pour in the milk and heavy cream while whisking constantly to avoid lumps. Stir in the minced garlic, salt, black pepper, thyme, and nutmeg. Continue to cook until the sauce thickens slightly, then remove it from the heat.
Arrange half of the sliced potatoes in an even layer at the bottom of your prepared baking dish. Pour half of the prepared cream sauce over the potatoes, spreading it out to cover them entirely. Repeat with the remaining potatoes and the rest of the sauce. Sprinkle the shredded parmesan cheese evenly over the top layer.
Cover the baking dish tightly with aluminum foil. Bake in the preheated oven for 45 minutes. Carefully remove the foil and continue baking for another 25 to 30 minutes, or until the potatoes are fork tender and the top is a beautiful golden brown color.
Remove the dish from the oven and let it sit for at least 10 to 15 minutes before serving. This resting period is crucial as it allows the sauce to set and thicken further, making it much easier to scoop out clean portions.
