Sweet Potato Layer Cake This is a Southern classic. 1 1/2 cups vegetable oil 2 cups granulated sugar 4 eggs, separated 1 1/2 cups finely shredded uncooked     sweet potato (about 1 medium) 1/4 cup hot water 1 teaspoon vanilla extract 2 1/2 cups cake flour 3 teaspoons baking powder 1 teaspoon ground cinnamon 1 teaspoon ground nutmeg 1/4 teaspoon salt 1 cup chopped pecans In a mixing bowl, beat oil and sugar. Add egg yolks, one at a time, beating well after each addition. Add sweet potato, water and vanilla extract; mix well. In a small mixing bowl, beat egg whites until stiff; fold into the sweet potato mixture. Combine flour, baking powder, cinnamon, nutmeg and salt; add to potato mixture. Stir in pecans. Pour into three greased 9-inch round cake pans. Bake at 350 degrees F for 22 to 27 minutes or until a wooden pick inserted near the center comes out clean. Cool for 10 minutes before removing to wire racks. Frosting 1/2 cup butter 1 1/3 cups granulated sugar 2 (5 ounce) cans evaporated milk 4 egg yolks, beaten 2 2/3 cups flaked coconut 1 cup chopped pecans 2 teaspoons vanilla extract Melt the butter in a saucepan; whisk in sugar, milk and egg yolks until smooth. Cook and stir over medium heat for 10 to 12 minutes or until thickened and bubbly. Remove from the heat; stir in the coconut, pecans and vanilla extract. Cool slightly. Place one cake layer on a serving plate; spread with a third of the frosting. Repeat layers.