Preheat the oven to 350°F. Lightly grease a 9' square baking pan (or a loaf pan if you prefer).
In a medium-sized bowl, beat together the brown sugar, milk, vegetable oil, eggs, and vanilla until smooth.
Whisk the baking powder, baking soda, salt, and cinnamon into the flour. Then, add the dry ingredients to the liquid ingredients in the bowl, stirring until combined.
Stir in the zucchini, walnuts, and raisins or chocolate chips.
Pour the batter into the prepared pan and sprinkle with sugar.
Bake the bread for 55 to 65 minutes, until a toothpick inserted into the centre comes out clean.