Preheat your oven to 300°F (150°C) and bake the all-purpose flour on a baking sheet for 8 minutes.

In a bowl, combine the baked flour with salt, softened butter, granulated sugar, vanilla extract, milk, and Christmas sprinkles. Mix until well combined, then freeze portions for later.

Increase the oven temperature to 350°F (175°C). Grease three 8-inch cake pans. Whisk together the flour, baking powder, baking soda, and salt in a bowl.

In another bowl, beat together the softened butter, oil, and sugar until fluffy, about 3-4 minutes. Gradually add eggs, sour cream, and buttermilk, mixing well. Fold in the dry ingredients until just combined.

Divide the batter evenly among the greased pans. Place frozen edible cookie dough discs on the batter, pressing them down slightly. Bake for 26 to 32 minutes, or until a toothpick comes out clean. Cool in the pans for 10 minutes before transferring to wire racks.

Beat the softened cream cheese and butter until smooth, then gradually add sifted powdered sugar. Mix in a pinch of salt and vanilla extract until fluffy.

Level the tops of the cooled cake layers if necessary. Stack the layers with cream cheese frosting in between. Frost the top and sides, decorating with extra cookie dough balls and sprinkles.