Preheat your oven to 300°F (150°C) to heat-treat the flour. Spread the all-purpose flour on a baking sheet and bake for 8 minutes, allowing it to cool completely.

In a mixing bowl, cream together room temperature unsalted butter and white granulated sugar on high speed for about 2 minutes until light and fluffy. Add pure vanilla extract and milk, mixing until well combined. Gradually incorporate the cooled flour mixture and a pinch of salt along with the Christmas sprinkles until just combined. Scoop, flatten into discs, and freeze 15 minutes.

Increase the oven temperature to 350°F (175°C) and prepare three 8-inch round cake pans by greasing and lining them with parchment paper. In a medium bowl, sift together all-purpose flour, baking powder, baking soda, and salt.

In a large mixing bowl, cream room temperature unsalted butter, canola oil, and granulated sugar for 2 minutes until fluffy. Then add pure vanilla extract, large eggs, and sour cream, mixing until combined. Gradually alternate adding the dry ingredients and buttermilk until the batter is smooth.

Carefully divide the vanilla cake batter evenly among the prepared cake pans. Gently press 5 frozen cookie dough discs into the center of each layer of batter to incorporate that delightful holiday twist.

Bake for 26-32 minutes, or until a toothpick inserted comes out clean. Allow the cakes to cool in the pans for about 10 minutes before transferring them to a wire rack to cool completely.

While the cakes are cooling, prepare the cream cheese frosting by beating softened unsalted butter on medium speed for 2 minutes until creamy. Gradually add cream cheese, continuing to beat until well combined. Incorporate powdered sugar, vanilla extract, and a pinch of salt until the frosting is fluffy.

Once the cakes have cooled, trim the tops if necessary for a flat surface. Place the first layer on a serving platter, spreading a generous layer of cream cheese frosting followed by a layer of edible cookie dough. Repeat with the second layer, then top with the final layer. Apply a light crumb coat of frosting around the entire cake.

Chill the assembled cake in the freezer for about 15 minutes to set. After chilling, frost the entire exterior with the remaining cream cheese frosting and decorate with cookie dough balls and sprinkles.

Slice into the Sugar Cookie Cake and serve at your holiday gatherings!