Preheat the oven to 325 degrees F. Grease and flour three 8 inch pans, adding a circle of parchment or wax paper to the bottom of each pan.
In a medium bowl, whisk the flour, baking powder, baking soda, and salt for 30 seconds and set aside.
In another bowl, add the buttermilk, oil, and vanilla extract. Set aside.
In the bowl of your mixer, add the butter and cream cheese and mix at medium speed until smooth.
Gradually add the sugar and mix at medium speed for 2-3 minutes.
Add the room temperature eggs one at a time, mixing until the yellow of the yolk disappears.
With the mixer on low speed, alternately add the flour mixture and the milk mixture, beginning and ending with the flour mixture (We did 3 additions of the dry mixture, 2 additions of wet). During this time, add a drop or two of coloring gel- start with less than you think you will need and adjust as needed.
Mix the batter just until well combined- be careful not to over-mix. Divide the batter between the three pans.
Bake at 325 degrees F for 25-28 minutes or until a toothpick inserted into the center comes out clean or with just a few crumbs attached. Let cool for 5-10 minutes in the pans on a wire rack before turning out.
This recipe makes 7 ½ cups of batter. Works for cupcakes also (although there will be little to no dome).