With a mixer, cream together the softened butter and cream cheese with the sugar until it is light and fluffy, about 3 minutes.
Add the eggs one at a time, mixing each until it is just incorporated.
On slow speed, stir in the flour and salt and then the cocoa powder and vanilla extract. Do not over mix.
Spread the cake batter into the prepared bundt or tube pan.
Bake until a skewer inserted into the middle of the cake comes out clean, about 1 1/2 hours, or until the cake reaches 210º F when checked with an internal digital read thermometer.
Notes
To store. Store the cake under a cake dome on the counter for up to 5 days.To freeze. Cool the cake completely. Wrap tightly with plastic wrap and then store in a freezer-safe zip-top bag for up to 3 months. To serve, thaw overnight and then slice and serve.