# What You'll Need:
→ Potatoes
01 - 2.5 pounds 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 extra for greasing
→ Aromatics & Seasonings
07 - 2 garlic cloves, minced
08 - 1/2 teaspoon freshly ground black pepper
09 - 1 1/2 teaspoons Kosher salt
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 generously with butter.
02 - In a medium saucepan, combine heavy cream, whole milk, minced garlic, Kosher salt, pepper, and nutmeg. Warm gently over medium-low heat until steaming but not boiling. Stir in half the thyme leaves.
03 - Spread half of the sliced potatoes evenly in the prepared dish. Pour half the cream mixture over the potatoes and sprinkle with half the Gruyere and half the Parmesan.
04 - Arrange remaining potatoes in an even layer. Pour over the remaining cream mixture. Top with the remaining Gruyere, Parmesan, and thyme. Dot surface with butter.
05 - Cover the dish tightly with foil and bake for 45 minutes.
06 - Remove foil and return dish to oven. Bake an additional 25 to 30 minutes, until potatoes are fork-tender and cheese is golden and bubbling.
07 - Transfer from oven and let rest at least 15 minutes before serving, allowing the sauce to thicken.
