Stir together first 5 ingredients in a medium bowl. Beat eggs and next 3 ingredients in a large mixing bowl at medium speed with an electric mixer until smooth. Add flour mixture, beating at low speed until blended. Fold in carrots, pineapple and nuts.
Pour batter into 3 greased and floured 9" round cake pans. Bake at 350° for 25 to 30 minutes or until a toothpick inserted in center comes out clean. Cool in pans on wire racks 10 minutes. Remove from pans and cool completely on wire racks.
Frosting: Beat cream cheese and butter at medium speed with an electric mixer until smooth. Gradually add powdered sugar, beating at low speed until light and fluffy. Stir in vanilla and nuts. Makes 6 3/4 cups.
Spread frosting between layers and on top and sides of cake.