• Preheat the oven to 325 degrees F. Grease a 10 cup bundt pan generously with non-stick cooking spray. This is optional, but you can dust the bundt pan with 2 tablespoons of cocoa powder. This will help keep the cake from sticking. Tap out an excess cocoa powder.
• In a large mixing bowl, add in the butter, granulated and brown sugar. Mix with a hand mixer on medium speed until creamed.
• Add in vanilla and eggs one at a time. Mix on medium and scrape down the sides of the bowl after each egg.
• In a medium bowl, add the flour, cocoa powder, baking powder, and baking soda. Whisk until incorporated. Set 1/4 cup of the dry ingredients aside in a small bowl and stir in the chocolate chips.
• Alternate adding the dry ingredients and sour cream to the butter/sugar mixture starting and ending with the dry ingredients. Scrape down the bowl after each addition.
• Fold in the zucchini and dry ingredients/milk chocolate chips into the batter until evenly distributed.
• Pour the batter into the prepared bundt pan and evenly spread out.
• Place in the oven for 65 to 70 minutes or until done. Place a skewer in the center of the cake and if it comes out clean or with a few moist crumbs, it's done!
• Remove from the oven and let cool for 15-20 minutes and turn out onto a cooling rack. Let the cake cool completely before pouring glaze on it.

Chocolate Glaze

• In a medium saucepan over low heat, add in cocoa powder, butter, and corn syrup. Stir until incorporated and the butter is melted.
• Stir in the vanilla and the powdered sugar until combined. The glaze will start to get thick.
• Add the hot water a teaspoon at a time and stir until combined. Do this until your glaze reaches the desired consistency.
• Turn the bundt cake out onto a cake plate and drizzle the glaze on the cake.