Potatoes Dauphinoise

INGREDIENTS

• 1 tablespoon unsalted butter, room temperature
• 2 1/2 pounds Yukon Gold potatoes
• 2 1/2 cups heavy cream
• 1 1/2 cups whole milk
• 1 garlic clove, smashed
• 1 teaspoon coarse salt
• 1/4 teaspoon ground white pepper
• 4 ounces Gruyere cheese
• 1/8 teaspoon freshly grated nutmeg