Combine flour, cocoa powder, baking soda, and salt in a bowl and whisk to combine. Set aside. In a large mixing bowl, whisk together sugar, oil, brown sugar, eggs, and vanilla until blended. Add sour cream and whisk to combine.
Add dry ingredients and mix just until blended. Stir in zucchini, chocolate chips, and coconut.
Bake for 50-60 minutes or until a toothpick comes out clean. (Bake mini loaves for about 35 minutes.) Cool in the pan on a rack for 10 minutes. Then remove from the pan and cool on a rack.