Preheat oven to 375 degrees F. Grease and flour two 9-inch round cake pans. In medium bowl combine flour, cinnamon, baking powder, baking soda and salt. In large mixer bowl beat sugar and oil until smooth. Beat in eggs. With mixer at low speed, add flour mixture and beat until just blended. Fold in carrots and nuts. Pour into prepared pans. Bake 35 minutes or until toothpick inserted in center comes out clean. Cool 10 minutes in pans. Invert onto wire racks to cool completely.
In large mixer bowl combine cream cheese, butter, vanilla and orange peel. Beat until light and smooth. Beat in confectioners' sugar until spreadable.
Place a cake layer on a plate. Spread on one third of the frosting: top with second layer. Frost top and sides with remaining frosting. Makes 16 servings. 575 calories each.