In a large bowl, combine the oil, sugars and eggs until well blended. Combine the flour, cinnamon, baking soda, salt and nutmeg; gradually add to creamed mixture until blended. Fold in the apples, walnuts and vanilla.
Pour into a greased and floured 10-in. fluted tube pan. Bake at 325° for 1-1/2 hours or until a toothpick inserted near the center comes out clean. Cool in pan 10 minutes before removing to a wire rack to cool completely.
In a small heavy saucepan over medium-low heat, cook and stir the brown sugar, cream, butter and salt until sugar is dissolved. Transfer to a small bowl; cool to room temperature. Beat in confectioners’ sugar until smooth; drizzle over cake. Sprinkle with walnuts if desired. Yield: 16 servings.