A layered casserole with sweet potato, apple and caramelized onion in a peppery cinnamon cream sauce with a brown sugar bread crumb topping.

Sweet Potato Gratin

5 Granny Smith apples
3 large sweet potatoes
2 large sweet onions
1/4 cup firmly packed light brown sugar - divided use
1/4 cup butter or margarine - divided use
2 teaspoons granulated sugar
2 teaspoons salt
2 teaspoons ground cinnamon
1/2 teaspoon pepper
3 cups whipping cream
1/4 cup fine, dry bread crumbs
2 tablespoons all-purpose flour

1. Peel first 3 ingredients. Cut apples and sweet potatoes into 1/8-inch-thick slices; set aside. cut onions crosswise in half, and cut each half into thin slices.
2. Combine sliced onion, 2 tablespoons light brown sugar, and 2 tablespoons butter in a large skillet. Cook over medium heat, stirring often, about 15 minutes or until onion is caramel colored. Set aside.
3. Combine granulated sugar and next 3 ingredients.
4. Layer one-third of apple and sweet potato slices alternately into a lightly greased 13 x 9 x 2-inch baking dish. Sprinkle with half of sugar mixture, and top with half of onion mixture. Repeat procedure, ending with apple and sweet potato slices. Pour whipping cream over top.
5. Stir together bread crumbs, flour, and remaining 2 tablespoons brown sugar; cut in remaining 2 tablespoons butter with a fork until crumbly. Sprinkle over casserole.
6. Bake at 350°F (175°C) for 45 minutes or until sweet potato is tender. Let stand 10 minutes.

Makes 6 to 8 servings.