Preheat oven to 350 degrees.
Prep your loaf pan. I used an 8 ½ x 4 ½ inch pan. You can use a pan spray or brush it with butter.
In a small bowl, mix together flour, baking powder, baking soda, and salt. Set aside.
In another larger bowl, add oil, butter, sugar. Mix them well, then add in the vanilla and egg. Mix to combine.
Add in zucchini and mashed bananas. Mix to combine. Add in dry ingredients, at this point be careful not to overmix.
Pour your batter into the prepared pan.
Bake for 50-60 minutes. Remove from the oven and allow it to cool for about 5-10 minutes. Then carefully invert to remove it from the pan.
I like to eat this hot, with plenty of butter, but it also really good cooled.
Now, sit back and enjoy. You deserve it!