Preheat the oven to 350 degrees F. Spray three 8-inch round cake pans with nonstick spray.
In a large mixing bowl, whisk together the flour, sugar, baking soda, cinnamon and salt. Add the eggs and oil, and stir just until combined, making sure to not over-beat the batter. Stir in the banana, pineapple, 1 cup pecans and vanilla. Evenly divide the batter between the prepared cake pans. Bake 30 to 35 minutes or until a toothpick inserted into the center comes out clean. Allow to cool for 10 minutes before turning out onto wire racks to cool completely.
CREAM CHEESE FROSTING:
In a large bowl, use an electric mixer to beat the cream cheese and butter together until light and fluffy. Add the powdered sugar, 1 cup at a time, scraping down the sides between each addition. Add the vanilla and beat for 2 to 3 minutes.
FROST THE CAKE:
Place one cake layer on a platter, and frost the top of it. Place the 2nd layer on top, and frost the top of that cake. Add the 3rd layer and frost the top and down the sides of the cake. Sprinkle the remaining pecans on top.