Preheat your fan oven to 160°C (325°F). Grease and line with parchment paper three 6" round cake tins. On the bottom of each pan put a layer of Oreo cookies. I used 7 cookies for each pan - six outside and one in the middle. Alternatively, you can use two 8" cake tins.
In a medium bowl sift together flour, cocoa powder, baking powder and salt. Add sugars, whisk until combined and set aside.
In a small bowl or measuring jug, whisk together eggs, vegetable oil, sour cream and vanilla extract. These are your wet ingredients.
In a small pot, bring your water to a boil or simmer, it's important that it's hot. Add the wet ingredients to dry ones, stir a little bit, it'll be somewhat dry. Then add the boiling water and whisk until combined. I usually add the water in two stages to minimize clumps forming.
Divide the batter evenly among the 3 tins and bake for 22-25 minutes or until skewer inserted in the middle comes out with few moist crumbs. Do not overbake it.
Once they're done, let the cakes cool for 10-15 minutes on a wire rack before removing them from the pans to cool completely.
Using a food processor, blitz Oreo cookies until fine crumb. You don't need to remove the filling, blitz everything together. Put it in a bowl and set aside.
In a small saucepan combine flour, sugar, salt and milk. Cook over medium-high heat, stirring constantly with a whisk until it thickens.
Once it's done, put a cling film over it touching the surface to prevent "skin" forming and let it cool to room temperature. This is your pudding base. You can do this in a fridge, but before using it let it come to room temperature
Using a stand mixer fitted with the paddle attachment, beat the butter for 5 minutes until it's pale and fluffy. Then add spoonful by spoonful of previously made pudding. Mix until it's all nicely incorporated and with no lumps. Add vanilla extract and mix until everything is combined.
If you wish to decorate the cake with black buttercream, now is the time to split it between colours and fillings.
Leave approximately ⅓ to ½ of the buttercream for filling and crumb coating the cake. Put in a small bowl and mix with Oreo crumbs.
Using leftover buttercream, leave about 2-3 tablespoons of white buttercream for the ghosts and some for the rosettes on top. The rest of the buttercream mix together with cooled melted dark chocolate in a bowl of a standing mixers. Using black gel food colouring paint it black. I needed almost half of my bottle, but it didn't affect the taste.
Using a cake leveler or a long serrated knife level the tops of your cakes if needed.
In the middle of your cake board or a serving plate put some buttercream to stop the cake from moving around.
Place one cake layer on a cake board or a serving plate. Using a small offset palette knife or a piping bag, spread the frosting over the cake. Top it with the next cake layer and repeat the process.
Place final layer on top, upside down, and do a thin crumb coat on the cake. Chill for 20-30 minutes in the fridge before final decorating.
Once cooled, frost and smooth the sides with the black buttercream using and if desired, put sprinkles around the bottom. Put the cake in the fridge until buttercream sets before putting on the ghosts.
Once the cake is chilled, put the white buttercream in a small piping bag with a round nozzle. I used Wilton 2A. Go around the cake, piping small balls where you want your ghosts to appear. Using a tip of small offset spatula press the white ball of frosting and pull it down. Using a small round nozzle pipe the eyes and mouth with black buttercream.
On the top, using a Wilton 1M tip pipe the rosettes in Halloween colours, I used orange and green.
If you don't have a stand mixer, you can use a hand mixer.
Not all ovens are the same. I suggest to check the cakes at 20 min mark and then adjust the baking time accordingly. Get to know your oven!
If putting Oreo cookies at the bottom of the cake batter, use a serrated knife when cutting the cake afterwards. Alternatively, you can blitz oreo cookies in a food processor to small chunks and mix with the batter.
If you still don't own one, I advise you to buy a kitchen scale - they're cheap and easy to use, and always guarantee the same results in baking!
I used almost half of black gel food colouring bottle, but it didn't affect the taste. Alternatively, you can use powder colouring or active charcoal - but I've never used it myself because I can't get to it.
Chocolate Oreo Layer Cake https://www.anasbakingchronicles.com/chocolate-oreo-cake/ October 29, 2018