In a stand mixer fitted with the paddle attachment, or in a large bowl with a handheld mixer, beat the butter and sugar together until light and fluffy.
½ Cup Unsalted Butter, 1 ½ Cups Granulated Sugar
Add in the eggs, oil, vanilla extract and vinegar and beat on high speed for 1-2 minutes.
2 Large Eggs, 1 Teaspoon White Vinegar, ½ Cup Neutral Oil, 2 Teaspoons Vanilla Extract
Add the dry ingredients in 3 additions, alternating with the buttermilk. Make sure to start and end with the dry ingredients.
1 Cup Buttermilk
Mix in your food coloring until you have your desired color.
Red Food Color
Stir in your Oreo cookies.
5 Oreo Cookies
Pour the cake batter into your prepared pans. Bake in the preheated oven for 25-30 minutes, or until a toothpick inserted in the middle of one of the cakes comes out clean.
In a stand mixer with the paddle attachment or a large bowl with a handheld mixer, beat the butter and confectioners' sugar together on low speed until combined.
If your frosting is too thick, you can add up to ¼ cup of heavy cream.
¼ Cup Heavy Cream
Once the cake layers are completely cool, frost and enjoy!
Video
Notes
My recipes have been developed and tested in metric grams. I highly recommend using a weighing scale and measuring out your ingredients the metric way. I have provided a conversion to US cups but please note that I haven’t tested the recipe with this method. Just click on ‘US Customary’ above the ingredients to see the cup measurements. I make sure that all of my ingredients are at room temperature before I start the recipe, so pull out all of the ingredients before you start baking.Cake Flour: Cake flour is different to all-purpose flour or plain flour because it has a lower protein content, that's going to make your cake much softer. If you don't have cake flour on hand, use all-purpose flour. I have tested it with all-purpose flour and it does work, but it isn't as soft! Please note if you're in the UK, cake flour is not self-rising flour! Just use plain flour. Red Food Gel: I used Americolor Super Red here. Salt: If you don’t have kosher salt, halve the amount of salt called for in the recipe. 1 teaspoon kosher salt = ½ teaspoon fine salt. Please note I'm using Diamond Crystal kosher salt and not Morton Salt, which is a different type of kosher salt (confusing, I know!) and is way more salty. Buttermilk: If you don’t have buttermilk, replace it with an equal amount of sour cream or full fat yogurt. You can also make your buttermilk, for every cup of buttermilk add 1 tablespoon of lemon juice to 1 cup of milk and let sit for 5 minutes. Cocoa Powder: make sure to use natural cocoa powder and not Dutch-processed cocoa powder. Not sure what type you have? Check the ingredients! If it mentions alkali or acidity regulators, it's Dutch-processed cocoa powder. Dutch-processed cocoa powder reacts differently to baking soda than natural cocoa powder. Storage: Keep tightly wrapped in the fridge for up to 5 days. Let it come to room temperature before eating.
Making Ahead: You can make the cake layers ahead of time. Bake them and then once completely cooled, wrap in plastic wrap tightly. Store in the fridge for up to 2 days or in the freezer for up to 2 months. If frozen, allow to defrost and come to room temperature before frosting the cake.