In a large bowl, whisk together flour, brown sugar, baking soda, baking powder, salt, cinnamon, and all-spice. In a small bowl, whisk together buttermilk, applesauce, oil, egg, and vanilla extract. Pour the wet ingredients over the dry ingredients and mix with a wooden spoon or spatula until just combined. Do not over mix. Gently stir in the grated apple, zucchini, and chopped apples.