Preheat oven to 350°F (175°C). Lightly grease a 9x5 inch loaf pan or line with parchment paper.
In a large bowl, whisk together sugar, oil, eggs, and vanilla until smooth.
In a separate bowl, combine flour, cocoa, baking soda, salt, and optional spices.
Stir dry ingredients into wet until just combined.
Fold in grated zucchini and chocolate chips.
Pour batter into pan, smooth top, and tap gently.
Bake 50–60 minutes, until a toothpick comes out clean.
Cool in pan 10 minutes, then transfer to a wire rack.