Potato and Swiss Cheese Gratin Recipe

Ingredients

• 2 tablespoons butter
• 2 tablespoons flour
• 3 cups whole milk
• 1 teaspoon salt
• 1/4 teaspoon pepper
• 1/2 teaspoon garlic powder
• 1/4 teaspoon nutmeg
• 1/4 teaspoon dried thyme
• 2 cups Swiss cheese, shredded
• 2 pounds Russet potatoes, washed, peeled, thinly sliced
• 1 cup sweet onion, peeled, thinly sliced