• Preheat your oven to 350°F (175°C) and allow it to heat for 15-20 minutes. Grease and flour three 8-inch round cake pans, and line the bottoms with circles of parchment paper for easy release.
• Crush the Oreos by placing them in a sealed plastic bag and smashing them with a rolling pin or crushing them between wax paper.
• In a medium bowl, whisk together the cake flour, baking powder, baking soda, and salt for about 30 seconds to fully combine. Set aside.
• In a separate bowl, mix together the buttermilk, vegetable oil, and vanilla extract. Set this liquid mixture aside as well.
• Using a stand mixer fitted with a paddle attachment, cream the butter on medium speed until smooth. Gradually add the sugar and continue mixing for 3 to 5 minutes, until the mixture becomes light and fluffy.
• One by one, add the eggs, making sure each is fully incorporated before adding the next.
• With the mixer on low, alternate between adding the dry flour mixture and the buttermilk mixture, starting and finishing with the dry ingredients. Mix just until the ingredients are well combined.
• Gently fold in the crushed Oreo crumbs, then evenly divide the batter between the prepared cake pans.
• Bake the cakes at 350°F for 25-30 minutes, or until a toothpick inserted into the center of the cake comes out clean or with just a few crumbs attached. If using 9-inch pans, check the cakes after 25 minutes. Allow the cakes to cool in their pans for 10 minutes before turning them out onto a wire rack to cool completely.

Oreo Whipped Cream Filling

• Place your mixing bowl and beaters in the freezer for 10 minutes, or refrigerate them for 20 minutes to chill.
• Add the cold heavy cream to the chilled bowl and whip on medium-high speed. As the cream thickens, add the powdered sugar and vanilla.
• Continue whipping until stiff peaks form (peaks should stand straight up when the beater is lifted). Avoid over-mixing, as this can give the cream a grainy texture.
• Gently fold in the crushed Oreos. This mixture yields approximately 2 cups of filling.

Vanilla Buttercream Frosting

• In a stand mixer, cream the butter until it’s smooth. Blend in the vanilla extract.
• Add half of the powdered sugar and most of the milk, and mix at medium speed until combined.
• Gradually add the remaining powdered sugar and milk, continuing to beat for 3 to 4 minutes. Occasionally scrape the sides of the bowl.
• Reduce the mixer speed to low and mix for 1 to 2 minutes to reduce any air bubbles, resulting in a smooth and velvety texture.
• This recipe yields approximately 4 ½ cups of frosting, enough to frost a two-layer 8 or 9-inch cake. If the frosting is too thick, add a little more milk; if it's too thin, add more powdered sugar.

Ganache Drip

• Place the chocolate in a microwave-safe bowl. Pour the heavy cream over the chocolate.
• Microwave the mixture for 1 minute. Stir, then microwave for an additional 30 seconds.
• Let the mixture sit for a minute, then stir until the chocolate is fully melted and the ganache is smooth and glossy. If needed, microwave in 10-15 second intervals until fully melted, allowing it to sit briefly between heating cycles.
• Once the ganache reaches a silky consistency, it's ready to use as a drip or decoration for the cake.