Preheat your oven to 350°F.
Generously grease the inside of the bundt pan with butter. Add flour to the pan and swirl it around to coat all of the butter. Turn the pan upside down and tap it gently to get rid of any excess flour.
In a medium bowl, whisk the flour, baking powder, baking soda, and salt. Set aside.
In a larger bowl, use a hand-held electric mixer or use a stand mixer with a paddle attachment to cream the butter with sugar until light and fluffy. Add the room temperature eggs, 1 at a time, and mix until just combined after each. Add the vanilla extract and sour cream and mix until smooth.
In a small bowl whisk the cocoa powder with the hot coffee or boiling water until smooth and add to the wet ingredients.
Add the dry ingredients to the wet ingredients and whisk until smooth. Fold in the chocolate chips and pour the batter into the prepared pan.
Bake for 45 minutes. A toothpick inserted into the center should come out clean.
Once the pan is cool enough to hold, cover it with a large plate and flip the pan over to invert the cake onto the plate.
Make the chocolate glaze: Melt the butter with the heavy cream in a medium pot. Stir in the vanilla extract and heat until the cream is just starting to boil.
Pour the cream mixture over the chopped chocolate and stir until the chocolate is melted and the glaze is smooth. Carefully spoon the glaze over the chocolate bundt cake. Top with more chocolate chips if desired and use a large serrated knife to slice and serve the cake.