Preheat oven to 350 degrees.
Grease two 8 inch baking pans with vegan butter or oil. Add a round of parchment paper to the bottom of each pan (optional).
In a large bowl mash the bananas until fairly smooth.
To the bananas, add brown sugar, grapeseed oil, applesauce, crushed pineapple, and vanilla extract. Stir to combine.
In a separate bowl combine the flour, baking powder, cinnamon, nutmeg, salt, and pecans.
Add the flour mixture to the banana mixture a little a time, stirring to combine. The batter will be thick and there is no need to mix until completely smooth.
Divide batter evenly between the cake pans and bake for 30-35 minutes or until a toothpick inserted comes out clean (check the cakes at about 30 minutes).
Let cakes cool completely before frosting. Cakes can be made one day ahead and kept in the refrigerator until it is time to frost.