Preheat oven to 325 degrees and spray a mini muffin pan with cooking spray.
Mix together flour, sugar, baking soda, chocolate chips and salt in a medium bowl.
In a large bowl, combine zucchini, the mashed banana, melted butter, egg, and vanilla. Add flour 4. mixture to the zucchini mixture and stir just until combined.
Using a cookie scoop or a tablespoon, fill the mini muffin pan and bake for 20-22 minutes or until a toothpick comes out clean.
Cool for 10 minutes then transfer the muffins to a cooling rack until completely cool.
*note - if the mixtures seems a bit dry (depending on the size of your banana) you can add in a tablespoon or two of water, milk, or almond milk.