Au Gratin Potatoes

Preheat oven to 350°F. In a large saucepan, melt the butter over low heat. Stir in flour, salt and pepper until smooth. Gradually add the milk, stirring to ensure there are no lumps. Bring to a boil. Cook and stir for 2 minutes or until thickened. Remove from the heat. Stir in the cheese until melted. Editor's Tip: Cooking the roux just long enough eliminates the taste of raw flour, but you don't want to take it too far. After you add the flour and seasonings to the butter, stir until the mixture looks bubbly and foamy, and then it should look like a thick paste. Using a whisk is fine, but consider using a rubber spatula to make sure the mixture doesn't collect in the corners and burn.

Add the potatoes and onion to the sauce; transfer to a greased 2-quart baking dish. Cover and bake for one hour.

Uncover and bake the potatoes for another 30 to 40 minutes or until the potatoes are tender. If desired, top with additional pepper.