To begin, preheat your oven to 350 and line a bread pan with parchment paper with two sides sticking out for easy removal (or spray with non-stick spray).
To a large mixing bowl, add your butter, brown sugar and applesauce and beat together with a mixer till creamy. Add your vanilla and eggs and beat again briefly to lightly incorporate them into your batter.
To the same bowl, add your flour, baking soda, baking powder, salt, cinnamon, and nutmeg. Stir the dry ingredients lightly together on top, and then stir everything together till you have a thick bread batter. Add your zucchini and gently fold it in.
Pour the batter into your bread pan and spread out evenly. Bake in the oven for 45-55 minutes, or till the top of the bread is set and a toothpick inserted comes out clean.
Let cool for at least one hour. Then remove from your pan, slice and devour!