Butter 10 cup Bundt cake pan and lightly dust with cocoa powder. Set aside.
In a large bowl mix flour, cocoa powder, sugar, baking powder, baking soda and salt. Stir well and set aside.
In a separate bowl mix buttermilk, coffee (or water), eggs and oil. Mix until well combined.
Add the wet mixture to the dry, whisk until incorporated. Pour the batter into prepared pan.
Bake for 40-45 minutes or until a toothpick comes out clean.
Let the cake cool in the pan for 10-15 minutes and then invert onto a rack. Let cool completely before glazing.
Make the ganache: chop the chocolate and place in a heatproof bowl. In a small saucepan heat the cream, when starts to simmer remove from heat and pour over the chocolate. Let sit for 1-2 minutes and stir until melted and smooth.
Pour the ganache over the cake, sprinkle some sprinkles on top and serve.