Beat butter, sugar, and cocoa until light and fluffy.
Add eggs one at a time beating well after each addition.
In another bowl mix flour, baking soda, and salt together.
Add flour mixture and buttermilk to the butter mixture in turns until combined. Do not over-beat.
Stir in vanilla and the dark chocolate.
Mix together in a small bowl the pistachios, ground coffee, and semi-sweet chocolate.
Pour 1/3 of cake batter into a well-greased bundt cake and sprinkle half of the pistachio mixture on top.
Repeat with another 1/3 cake batter and the other half of the pistachio mix. Top with remaining cake batter.
Bake at 325 degrees for 1 hour or until toothpick comes out clean and the cake is pulling away from the sides.
Top with chocolate ganache, pistachios, and cocoa nibs (or additional chocolate bits)