Potato Gratin

Most gratins call for béchamel sauce, which of course is thickened with flour. Because potatoes have enough starch of their own, you can simply use half-and-half, cream, or a combination of cream and milk over the layers of sliced potatoes. Some recipes insist that you rinse the potatoes after slicing them. Others say that the starch adhering to the slices is essential for the gratin to hold together. In fact, it doesn’t make much difference whether you rinse or not. If you want to slice th