In a small bowl, combine the nuts, brown sugar, butter and cinnamon; set aside. In a large bowl, cream butter and sugar until light and crumbly. Beat in the egg yolks, oil, applesauce and vanilla. Combine the dry ingredients; add to the sugar mixture alternately with sour cream, beating well after each addition.
In another bowl, beat egg whites on high speed until stiff peaks form. Fold into batter.
Pour half of the batter into a 10-in. fluted tube pan coated with cooking spray and floured; sprinkle with nut mixture. Pour in remaining batter.
Bake at 350° for 45-55 minutes or until a toothpick inserted in the center comes out clean. Cool for 10 minutes before removing from pan to a wire rack to cool completely. Sprinkle with confectioners' sugar.