Preheat the oven to 325F and place a rack just below center.
Butter and flour (or spray and flour) a 12-cup Bundt or tube pan. Set aside.
Cream the butter, shortening and sugar together in a stand mixer on medium speed for about four minutes or until it is white and fluffy. Scrape bowl occasionally.
Add the cream cheese and beat again until light and fluffy. Scrape bowl occasionally.
Alternately add the flour and eggs, beginning and ending with the flour. (One cup flour then three eggs, one cup flour and the last three eggs, the final cup of flour). Make each addition after the previous has just been combined. Scrape the sides occasionally.
Add the vanilla, mix just until combined. Remove the bowl from the mixer and using the spatula you were scraping the side with, scrape up from the bottom to make sure all of the ingredients are incorporated.
Scoop the batter into the prepared pan (this is too thick to pour). Even out the top. Bake for 1 hour and 15 minutes or until a wooden toothpick comes out clean.
Cool in the pan on a rack for ten minutes and then remove from the pan, put back on the rack (top side up) and cool completely.