Prepare the Bundt Pan: Preheat the oven to 350°F (175°C). Grease the Bundt pan with cooking spray.
Mix the Cake Batter: Combine the chocolate cake mix, pudding mix, eggs, sour cream, oil, and water in a large bowl. Beat until smooth, about 2 minutes. Fold in chocolate chips.
Bake: Pour the batter into the Bundt pan. Bake at 350°F for 50-55 minutes, or until a toothpick comes out clean.
Cool the Cake: Allow the cake to cool in the pan for 10-15 minutes, then invert onto a cooling rack to cool completely.
Make the Ganache: Heat the heavy cream in a saucepan over medium-low heat until it simmers. Remove from heat and whisk in the chocolate chips until smooth. Let cool for 15-20 minutes.
Drizzle Ganache: Pour the ganache over the cooled cake and allow it to set for a few minutes before slicing.