Preheat the oven to 350°F (175°C).

In a large bowl, combine flour, sugar, baking soda, cinnamon, and salt.

Add vegetable oil and eggs to the dry ingredients, mixing well.

Fold in mashed bananas, crushed pineapple, and chopped nuts.

Pour the batter into greased and floured cake pans.

Bake for 30 minutes or until a toothpick inserted comes out clean.

Allow cakes to cool before making the frosting.

For the frosting, beat together cream cheese, softened butter, powdered sugar, and vanilla extract until smooth.

Frost the cooled cakes and serve.