For most of the birthdays in the house I make some form of vegan chocolate cake. It’s almost always over-the-top extravagant, with its four layers of sponge and insanely-rich chocolate filling and surrounded by even more chocolate. The family love them, so I thought I’d share one of them with you here.
I’ve used Oreo cookies as both a topping and a filling for this cake (not the healthiest choice, I know, but it’s only supposed to be on special occasions). The cake itself is regular vegan chocolate sponge, but the filling and topping uses aquafaba to give it a light, fluffy texture. I’ve made a 5 minute instructional video with this recipe, so that you can see each step as you go along.
Prep time: about 1 hour. Cooking time: about 90 minutes, plus cooling and setting time.
Serves up to 12.
For the Chocolate Sponge:
- 600g unrefined sugar
- 600g vegan margarine, plus extra for greasing
- 2 tbsp chia seeds
- 50ml cold water
- 500g self-raising flour
- 2 tsp baking powder
- ½ tsp salt
- 100g cocoa powder
- 2 tsp vanilla extract
- 100ml plant-based milk (I used oat)
- 150g dark chocolate, broken into small pieces
For the Chocolate Filling and Topping:
- 1 can chickpea water (aquafaba)
- 1 tsp cream of tartar
- 2 tbsp unrefined sugar
- 200g Oreos (I used Oreo thins)
- 200ml vegan cream
- 200g dark chocolate, melted
- 80g vegan margarine, room temperature
Additional topping (if required):
- 200g dark chocolate, melted
- 100g vegan margarine, at room temperature
- 50ml vegan cream
You will also need about 32 Oreo Thins to put on top of the cake.
Preheat the oven to gas 5/190C/375F and grease and line with baking paper either 2 or 4 lose-bottomed cake tins, approximately 8 inches (20cm) in diameter.
To make the sponge layers, put the margarine and sugar into a large mixing bowl and cream together using an electric whisk, until the mixture is light and fluffy (about 5 minutes).
Put the chia seeds into a small bowl and add the 50ml of cold water. Stir together and leave for 10 minutes, until you get a gloopy mixture.
In the meantime, add the flour, baking powder, salt and cocoa powder to the sugar and butter mix and stir until fully combined. Add the vanilla extract, the plant-based milk and the chia seed mix and stir thoroughly. Now add the chocolate pieces and stir again, then divide the mixture into 4 and put a quarter of it into each lined cake tin. If you are using 4 tins, then you can fill them all straight away. If you are using two tins, then just use half the mixture for now. You will only be cooking two cakes at a time anyway.
Place two of the cakes in the middle of the oven and bake for 40-45 minutes, until risen and cooked through. Allow the cooked cakes to cool for 5 minutes, then turn them out onto a cooling rack.
Now either grease and line the same cake tins, or use two new ones. Divide the remaining half of the mixture between those tins and bake in the oven again for the same amount of time.
When all four sponge layers have cooled you can begin making the filling.
Pour the chickpea water into a mixing bowl, add the cream of tartar and whisk on a medium speed for about 5 minutes, until it begins to stiffen. Add the sugar and whisk on a slightly higher speed for another 5-6 minutes, until you have firm, stiff peaks and you can turn the bowl upside down without any movement from the aquafaba.
Put the Oreos and cream in a blender jug and blend until completely smooth. Pour this into the aquafaba and mix thoroughly.
Now stir the margarine into the melted chocolate in a small bowl, until they are fully combined, then stir this into the aquafaba mixture.
Allow to cool for 30 minutes, then place the bottom sponge onto a plate or cake board. Put a couple of spoons of the filling mixture on top and spread it out with a palette knife. Lay the second sponge on top and repeat the process. Do this until you have all four layers stacked up and then spoon the filling onto the top layer. Spread it out again and allow it to run down the sides, spreading it around the cake edges with the palette knife. I found that this left me a little short around the edges. If this happens to you, or if you just want more chocolate, then make an additional topping buy whisking the three additional topping ingredients together, allowing it to cool and thicken up, and then spreading it around the cake.
Top the cake with Oreo Thins, as shown in the picture and video, and add any extra decoration that you fancy. Allow at least two hours to set before serving.