# What You Need:
→ Potatoes
01 - 2.5 lbs Yukon Gold or Russet potatoes, peeled and sliced 1/8-inch thick
→ Dairy
02 - 2 cups heavy cream
03 - 1 cup whole milk
04 - 2 cups Gruyere cheese, grated
05 - 1/2 cup Parmesan cheese, grated
06 - 2 tablespoons unsalted butter, plus more for greasing
→ Aromatics & Seasonings
07 - 2 cloves garlic, minced
08 - 1 1/2 teaspoons Kosher salt
09 - 1/2 teaspoon freshly ground black pepper
10 - 1/4 teaspoon ground nutmeg
11 - 1 tablespoon fresh thyme leaves or 1 teaspoon dried thyme
# How to Make It:
01 - Preheat oven to 375°F. Grease a 9x13-inch baking dish with unsalted butter.
02 - Combine heavy cream, whole milk, garlic, Kosher salt, black pepper, and nutmeg in a medium saucepan. Warm gently over medium-low heat until steaming, stirring in half the thyme. Do not allow to boil.
03 - Arrange half the sliced potatoes evenly in the prepared baking dish.
04 - Pour half the cream mixture over the potatoes. Sprinkle with half the Gruyere and half the Parmesan cheese.
05 - Layer the remaining potatoes on top. Pour over the rest of the cream mixture.
06 - Scatter remaining Gruyere, Parmesan, and thyme over the surface. Dot with unsalted butter.
07 - Cover dish tightly with foil and bake for 45 minutes.
08 - Remove foil and continue baking for 25-30 minutes until potatoes are tender and the top is golden and bubbling.
09 - Allow to rest at least 15 minutes to let sauce thicken before portioning.
