Golden Scalloped Potatoes

• 2 pounds medium to large boiling potatoes, such as Yukon gold (see Cooks' Notes)
• 2 tablespoons unsalted butter, melted
• 2 tablespoons all-purpose flour
• Salt
• Freshly ground black pepper
• 2 cups milk
• 4 ounces sharp Cheddar or Gruyere, coarsely grated (1 cup; optional)
• Mandoline or vegetable slicer; 2-quart flameproof shallow baking dish (not glass)

1. Heat oven to 375u0b0F with rack in middle. Butter baking dish.
2. Peel and thinly slice potatoes into a large bowl and toss with butter. Spread potatoes in an even layer in the baking dish.
3. Put flour, 1 teaspoon salt, and 1/4 teaspoon pepper in a heavy medium saucepan and slowly whisk in milk until the mixture is smooth.
4. Bring milk mixture just to a boil over medium heat, whisking constantly (it will thicken slightly), and pour it over the potatoes. Cover pan tightly with foil and bake in oven until potatoes are tender, 35 to 40 minutes.
5. Remove foil and sprinkle with cheese, if using. Reset oven to broil and broil potatoes, about 4 to 5 inches from heat, until browned and bubbling, 2 to 3 minutes.

boiling potatoes, unsalted butter, flour, salt, freshly ground black pepper, milk, gruyuere, mandoline

Taken from www.epicurious.com/recipes/food/views/golden-scalloped-potatoes-368569 (may not work)