One of Henry’s (and his sister, Alice’s) favourite dishes from childhood, this is decadent and packed with sweetness – perfect for the festive season! It firms up a little as it cools so make it a day in advance. Upgrade the decoration by shaving over some chocolate with a Microplane or by melting a thin layer of chocolate onto a baking tray, letting it harden and scraping it off. You can also adorn with holly and cranberries.
SERVES 8–10
170ml aquafaba (the drained water from 1–2 x 400g tins chickpeas)
½ tsp cream of tartar
150g light soft brown sugar
50g cocoa powder
100g plain flour
1 tsp bicarbonate of soda
¼ tsp ground cinnamon
¼ tsp salt
2 tsp vanilla extract
1 tsp cider vinegar
75ml light olive oil
unsweetened plant-based milk, for thinning, optional
icing sugar, for dusting
cocoa powder, for dusting
50g dark chocolate, for grating over the top
FOR THE FROSTING
400g dark chocolate
250g icing sugar
400ml coconut cream
100g cocoa powder
a pinch of salt
Preheat oven to 180°C | Grease a 23 x 33cm Swiss roll tin or a 20 x 30cm baking tray with light olive oil, line with parchment paper and grease again | Kettle boiled | Stand mixer or food processor fitted with the whisk or beater attachment | Medium saucepan | Heatproof bowl
Pour the aquafaba into the mixer or food processor and switch it on to high | With the motor running, add the cream of tartar and leave to run for 3 minutes, until the mixture becomes foamy and starts to thicken | Add the soft brown sugar, a tablespoon at a time, waiting for the sugar to be completely incorporated before adding more | Run for 2–3 more minutes then switch off the machine and remove the bowl
In a separate bowl, sift together the cocoa powder, flour, bicarbonate of soda, cinnamon and salt | Stir together to mix thoroughly | In another bowl combine the vanilla extract, cider vinegar and oil | Pour the dry ingredients into the aquafaba mix and gently fold together | Once fully combined, add the wet ingredients and mix well | Thin the mixture with a little milk if necessary | Pour the batter into the prepared tin or baking tray and spread it out evenly with a spatula or the back of a metal spoon
Put the tin in the oven for 20 minutes | Remove and run a knife around the edges of the sponge to loosen it | Leave to cool completely, then transfer to a chopping board | Cut lengthways into 3 rectangles, one slightly thicker than the other, about 8cm, 8cm and 7cm wide
To make the frosting, pour hot water into the saucepan, about 3cm deep and bring to the boil | Reduce to a simmer | Put the heatproof bowl on top, ensuring the water doesn’t touch the bottom | Break the chocolate into the bowl and leave to melt | Remove and leave to cool a little | Alternatively, melt the chocolate in the microwave | Add the cooled (but not cold) chocolate to the mixer or food processor, pour in the remaining frosting ingredients and beat to a smooth, thick frosting
Layer the cake slices on top of each other with the smaller one on top | Cut off a quarter of the cake at a 45-degree angle | Separate the slices and place one large slice on a serving board | Lay a large ‘branch’ piece alongside at an angle | Spread with frosting | Lay the other large slices over the top and spread with frosting | Top with the final, smaller pieces | Cover the whole cake with the remaining frosting and use a fork to create bark patterns | Dust with icing sugar and cocoa powder | Leave to firm up for at least an hour then grate over the chocolate and serve