Preheat the oven to 325 degrees F. Prepare a 12-cup nonstick bundt pan by spraying it with nonstick spray and then coating the sides with flour. Set aside.
In a medium size bowl, whisk together the cake flour, baking powder and salt. Set aside.
In the bowl of a stand mixer, fitted with the paddle attachment, beat the butter, oil, and sugar on high until fluffy and smooth, about 5 minutes.
Add the eggs and the egg whites, one at a time to the bowl and beat on medium until well incorporated. Add the sour cream and beat on medium speed for a minute or so. It may look curdled, don't stress.
Turn the mixer on low and add 1/3 of the flour mixture to the butter mixture and mix until fully incorporated. Then add half of the buttermilk and blend well, followed by another 1/3 of the flour mixture, the second half of the buttermilk and lastly, add the remaining flour mixture and mix until incorporated.
Add the vanilla extract and beat on low until incorporated. Scrape down the sides of the bowl and mix on low for another 30 seconds. Fold in the sprinkles.
Pour the cake batter into the prepared bundt pan and bake for 50 to 60 minutes. The cake is done when a toothpick inserted in the center of the cake comes out with a few moist crumbs on it.
Let the bundt pan cool completely in the pan before inverting onto your cake stand.