Preheat your oven to 350°F (175°C) and grease three 9-inch round cake pans.
In a large bowl, mix flour, sugar, baking soda, and salt.
In another bowl, combine mashed bananas, crushed pineapple, vegetable oil, and eggs.
Mix wet and dry ingredients until just combined.
Fold in chopped pecans and vanilla extract.
Divide batter among the prepared pans.
Bake for 30-35 minutes or until a toothpick comes out clean.
Allow cakes to cool in pans for 10 minutes, then transfer to wire racks.
Frost with cream cheese frosting once cooled.
Decorate with additional pecans if desired.