Seasoned with garlic and lightened with egg whites, a potato souffle is delightfully puffy out of the oven.
Heat oven to 375 degrees. Butter an 8-inch-long, 1/4-inch-deep oval gratin dish. Coat with bread crumbs, and set the dish aside.
In a large bowl, whisk together the potatoes, egg yolks, cream, Parmesan cheese, and garlic until creamy and well combined. Season with salt and pepper, and set the potato mixture aside.
Place egg whites and a pinch of salt in the bowl of an electric mixer fitted with the whisk attachment. Whip on medium speed until the whites are glossy and stiff.
Fold the egg whites into the potato mixture. Transfer mixture to the prepared gratin dish, and bake until golden and puffy, about 40 minutes. Top with nutmeg, and serve.
Sprinkle a little more grated Parmesan over the souffle before baking.