Preheat oven to 375°F / 170°C. Prepare a 12-cup muffin tin.
Mash the bananas in a medium bowl, then whisk in the egg, followed by the honey, olive oil, and vanilla. Fold in the grated zucchini.
In a large mixing bowl, combine the flour, oats, matcha, baking powder, baking soda, and salt.
Add the wet ingredients to the dry ingredients, folding just until incorporated - don’t over-mix or your muffins will be tough. Scoop into the prepared muffin tin and place in the oven.
Bake for about 20-25 minutes until a toothpick inserted into the centre comes out clean. Transfer muffins to a cooling wrack, and let cool completely. Say thank you, and enjoy. Store leftovers at room temperature for 3 days, or in the fridge for a week. Freezes well.