Preheat your oven to 350 degrees F. Grease a 9x5-inch loaf pan and set it aside.
In a large mixing bowl, whisk together the all-purpose flour, baking powder, baking soda, salt, and ground cinnamon until well combined.
In a separate bowl, mix together the granulated sugar, brown sugar, coconut oil, mashed bananas, grated zucchini, eggs, and vanilla extract until smooth.
Gradually add the wet ingredients to the dry ingredients, stirring gently until just combined. Be careful not to overmix the batter to maintain a tender texture.
If desired, fold in chopped nuts, chocolate chips, or raisins for added flavor and texture.
Pour the batter into the greased loaf pan, smoothing the top with a spatula.
Bake the banana zucchini bread for approximately 40-45 minutes or until a toothpick inserted into the center comes out clean.
Remove the bread from the oven and let it cool in the pan for about 10-15 minutes.
Transfer the bread to a wire rack to cool completely before slicing.
Slice and serve the bread as a delightful breakfast, snack, or dessert option.