Heat oven to 350 and prepare three 8-inch round cake pans.
In a large bowl sift together the flour, baking soda, baking powder, cinnamon, and salt.
In a stand mixer on low speed add in the sugar, eggs, oil, vanilla, and banana. Mix on medium speed for about 1 minute, or until fully combined.
One cup at a time add the flour mixture into the sugar mixture. Mix until just incorporated and remove bowl from mixer.
Stir in the drained and shredded zucchini.
*I prefer to not peel the green skin off on my zucchini, but you certainly can. If you have a very large zucchini, remove any seeds prior to grating.
Bake for 22-26 minutes, or until inserted toothpick is removed mostly clean.