Ingredients
8 cups sliced peeled potatoes (1/4-inch slices)3 medium leeks (white portion only), cut into 1/2-inch slices2 tablespoons butter3 tablespoons all-purpose flour1/2 teaspoon salt1/8 teaspoon pepper1-1/3 cups 2% milk4 ounces Gruyere or Swiss cheese, shredded1/8 teaspoon ground nutmegCRUMB TOPPING:1/3 cup dry bread crumbs2 tablespoons butter, melted1/4 cup shredded cheddar cheeseChopped chives, optional
Preparation
Preheat oven to 325°. Place potatoes in a Dutch oven and cover with water. Bring to a boil. Add leeks; return to a boil. Cover and cook for 5 minutes. Drain and pat dry. Place in a greased 13x9-in. baking dish.
In a large saucepan over medium heat, melt butter. Stir in flour, salt and pepper until smooth; gradually add milk. Bring to a boil; cook and stir until thickened, 1-2 minutes. Stir in cheese and nutmeg until cheese is melted. Pour over potato mixture. Toss bread crumbs and butter; sprinkle over the top.
Cover and bake for 40 minutes. Uncover; sprinkle with cheddar cheese. Bake, uncovered, until potatoes are tender, 15-20 minutes. If desired, top with chives.
