Preheat oven to 350 degrees F.
Liberally spray a muffin tin with cooking spray or grease with coconut oil.
Grate zucchini. Squeeze out excess water. Set aside.
In a large bowl, whisk together the brown sugar, applesauce, maple syrup, softened butter, and vanilla. Add zucchini and fold in with a spatula.
Add in the flour, baking powder, baking soda, cinnamon, nutmeg, cloves, and salt. Stir just until no dry ingredients remains.
If adding, walnuts, or any optional ingredients, add now. Fold to combine. Do not over mix.
Pour batter into greased muffin tins until ¾ full.
Bake for 30 to 40 minutes or until a toothpick inserted into the center of the bread comes out clean.
Remove from the oven and let cool for 10-15 minutes.
Remove from the tins and transfer to cool completely.
Store in an air tight container.