Combine the first 5 ingredients in a large bowl. Add eggs and oil, stirring until dry ingredients are moistened. Do not beat. Stir in vanilla, pineapple, 1 cup of pecans and bananas. Pour batter into 3 greased and floured 9 inch pans. Bake at 350 degrees for 25 to 30 minutes or until a wooden toothpick comes out clean, you know the routine by now. Cool in pans for 10 minutes; remove from pans and let cool on wire racks. Stir 1/2 cup of pecans in cream cheese frosting or reserve them for the top and the sides.