Preheat oven to 325°F (163°C). Generously grease a 10-12 cup bundt pan with butter or nonstick spray. If you want a smaller bundt cake, you can split it into 2 bundt pans.
In a medium bowl, mix together cake flour, baking powder and salt. Set aside. This is the dry mixture.
In a stand mixer, beat the butter and sugar on high speed until smooth and creamy, about 2 minutes. Scrape down the sides and up the bottom of the bowl with a rubber spatula.
Add the cream cheese and beat on high speed until completely smooth and combined.
Add the sour cream and vanilla and beat on high speed until combined and creamy.
On a low speed, add in the eggs one a time and mix well.
Add the dry mixture. Beat on medium and be careful not to overmix. Using a rubber spatula to make sure that the bottom of the bowl is combined.
Pour/spoon batter evenly into prepared pan. Bang the pan on the counter once or twice to bring up any air bubbles.
Bake for 75-95 minutes. Make sure to check with a skewer for doneness at the 60 minute mark. The cake is done when the inserted skewer comes out dry.
Remove cake from the oven and allow to cool for 10 minutes on a wire rack. Then invert the pound cake onto a wire rack or serving dish. Allow to cool completely.