Method (Cakes)

1. Preheat your oven to 180°C fan and line three 8 inch loose base / push up cake tins with greaseproof paper. If you don’t have 3 cake tins you will have to bake the cakes separately. Just cover the unused batter with a damp tea towel until you’re ready to use it.
2. In a bowl, combine the dairy-free milk with the apple cider vinegar and whisk until fully combined. Set aside for 10 minutes to curdle. This creates a vegan ‘buttermilk’.
3. In a large mixing bowl, sift the flour, sugar, baking powder and bicarbonate of soda. Mix well to combine.
4. Add the oil and vanilla into the ‘buttermilk’ and whisk to combine.
5. Add the wet ingredients into the dry ingredients and mix.
6. Fold in the ground up / chopped oreo cookies. 
7. Pour equal amounts of batter into the lined cake tins. Make sure to tap the tins on the worktop to remove any air bubbles.
8. Pop the cakes into the centre of the preheated oven and bake for around 25-30 minutes. You will know they are done when you put a knife or skewer in to the centre of the cake and it comes out clean and they are springy to the touch.
9. Place the cakes on a cooling rack and allow to cool slightly before removing them from the tins. Leave the cakes to cool fully on the cooling rack.  Once cool, pop them into a sealed container to keep them fresh before frosting.

Method (buttercream)

1. In a large mixing bowl, add in the dairy-free butter and cream cheese, whip until creamy. I use a stand mixer with a balloon whisk attachment, a hand mixer will work great too.
2. Sift in the icing sugar and add in the ground oreo cookies. Whip on high speed for around 5-8 minutes to incorporate it. If the buttercream is too thick, add some more chunks of cold butter. if it’s too soft, add more icing sugar. You want it smooth, creamy and airy.
3. Place one of the cakes on a serving plate or cake stand. Dollop or pipe some of the buttercream on top and spread out until even using an off-set spatula or pallet knife.
4. Optional: Add a sprinkle of ground oreos in between the layer. Place the next cake layer on top and repeat.
5. Give the entire cake a crumb coat (thin layer of buttercream to help lock in any crumbs to prevent them in the final coat, using a cake scraper or pallet knife to get the sides smooth.
6. Place the cake into the fridge to set for 15-20 minutes. You want the buttercream to be firm, this will make the final coat and applying the decorations easier.
7. Whip up a batch of the black buttercream. Remove the cake from the fridge and apply a second/final coat, this time making it thicker, then using a cake scraper to make the edges of cake smooth. Use a offset spatula to create a decorative effect around the edge of the cake (refer to video for example).
8. Transfer any left over buttercream into a piping bag fitted with a medium sized star tip nozzle.
9. Pipe swirls of the buttercream around the top edges of the cake.

Method (oreo bats)

1. Twist mini Oreos apart gently to separate the halves.
2. Scrape off the cream with a knife (or leave it if you like it).
3. Twist a regular sized oreo in half then carefully cut each half in half (into semicircles) to make bat wings. You’ll need 2 semicircle halves per bat.
4. Dab a little frosting on the back of each “wing” piece.
5. Gently press the wings onto the mini oreo (at an angle so they look like spread wings) then dab on more frosting and add the other mini oreo on top to create the bat. Hold for a few seconds to help it stick.
6. Pipe two small dabs of white chocolate on the top of the Oreo body, with 2 smaller dots of dark chocolate in the middle to create the eyes.
7. Pop in the freezer for 5-10 minutes to set then place on the cake to decorate.
8. Slice, serve and enjoy!