Combine egg and sugar in a medium mixing bowl. Beat until light and fluffy. Sift together flour, baking powder, and salt; add to egg mixture, and beat well. Stir in apple, raisins, pecans, and vanilla.
Pour batter into a well- greased 1-quart casserole. Bake at 350° for 30 minutes. Spoon into individual serving dishes, and top with whipped cream.