Preheat the oven to 350 degrees. Grease the muffin tins well.
Finely grate the zucchini on the small side of the grater. Using toilet paper or cheesecloth squeeze out the excess liquid and measure out one cup, lightly packed.
In a small bowl mash the banana very well and measure out 3 tablespoons. Add the yogurt, vanilla, egg, coconut oil (melted and cooled), and honey. Add in the coconut sugar and stir to combine.
In a separate bowl stir together the oat flour, spelt flour, baking soda, salt and cinnamon.
Add the dry ingredients to the wet ingredients and mix until just combined. Do not over mix or the result will be dense muffins. Add in zucchini and stir gently to incorporate.
Divid the muffins into baking tinsa nd bake for 18-22 minutes for regular muffin pan or until toothpick inserted comes out clean. Let cool for 5-10 minutes in pan before removing onto a cooling rack.
Store in an airtight container for up to a week (depending on temperature). You can also refrigerate and let muffins warm to room temperature (30 mins-1 hour) before eating.