Preheat oven to 350 degrees. Grate the zucchinis and set on paper towels to absorb excess moisture. Between 2-3 cups is perfect.
Combine sugar, eggs, applesauce, zucchini, butter and vanilla in a large bowl.
Combine the chocolate chips with a couple tablespoons of the flour to keep them from sinking to the bottom while the cake is baking.
Stir in the flour, baking soda, salt, cinnamon, cocoa powder and chocolate chips. Stir until all of the ingredients are thoroughly combined.
Pour the batter into a well-greased bundt pan. Bake the cake for 60-70 minutes or until an inserted toothpick comes out clean. Let the cake cool for 10 minutes before inverting onto a plate.
Chocolate Glaze: Combine the butter, chocolate chips and corn syrup in a microwavable dish. I use my pyrex glass measuring cup because it makies it easy to drizzle the glaze over the cake. Heat in the microwave in 30 second intervals at 50% power, stirring in between, until nicely melted. Pour over cake and enjoy!