• Preheat oven to 350F, coat a bundt pan with cooking spray and then flour. Invert and bang to remove excess flour.
• Whisk together flour, cocoa powder, baking soda, baking powder, and salt. set aside
• In the bowl of a stand up mixer with a paddle attachment cream together sugars and butter, add eggs one at a time and mix well after each addition, add sour cream and vanilla and mix well. Add dry ingredients 1/2 a cup at a time and mix well, then fold in zucchini.
• Pour mixture into prepared bundt pan and bake 45 - 50 mins. or until cake tester comes out clean.
• allow to cool in pan for 15 mins. invert onto wire rack and let cool.

For the glaze:

• Melt the butter in a small sauce pan over low heat, remove from heat and add chocolate chips and stir until melted, add the corn syrup and vanilla, immediately pour glaze over the cake allowing it to run down the sides.
• Allow glaze to cool completely before serving.