Suitable for vegans and delicious for everyone, this is the cake to make for a celebration. Aquafaba is the water from a can of chickpeas and behaves just like egg white.
Heat the oven to 180°C/160°C fan/350°F/Gas 4.
Make the sponge. In a large mixing bowl, stir together the flour, sugar, cacao, baking powder, salt and hazelnuts.
In a medium mixing bowl, using a balloon whisk, combine the melted spread, soy coffee & hazelnut milk, walnut oil and xanthan gum. Dissolve the coffee in the boiling water, then whisk it into the bowl with the other liquid ingredients.
Combine the wet and dry ingredients to a smooth batter, then divide the batter equally between the 3 tins. Bake the sponges for 30–35 minutes, until just firm to the touch and a metal skewer inserted into the centres comes out clean. Leave to cool in the tins for 5 minutes, then turn out onto a wire rack to cool completely.
Make the meringues. Reduce the oven temperature to 110°C/90°C fan/225°F/Gas ½. Place the aquafaba in the bowl of the electric stand mixer fitted with the whisk and whisk on high speed for about 5 minutes, until doubled in size and thick and foamy.
With the whisk on slow, add the icing sugar and xanthan gum, then increase the speed to maximum and whisk for about 10 minutes, until the mixture forms stiff peaks.
Place the mixture into the large piping bag fitted with a large star nozzle. Pipe meringue kisses over the baking trays (you’ll have many more meringues than you need – you can freeze the spares once baked; or keep them in an airtight container for 1 week).
Bake the meringues for 90 minutes, until dried out. Allow to cool, then dust with gold lustre powder.
Meanwhile, make the ganache. Place the chocolate in a heatproof bowl. Warm the coconut cream and salt in a pan over a low heat until starting to bubble around the edge. Pour the coconut cream over the chocolate, leave for 5 minutes, then mix until smooth. Stir in the Tia Maria. Cover with cling film and chill for about 2 hours, until set.
Make the truffles. Place the chocolate buttons in a heatproof bowl. Warm the coconut cream in a pan over a low heat until starting to bubble around the edge. Pour the coconut cream over the chocolate, leave for 5 minutes, then mix until smooth. Pour into the square container and chill to set.
Put the chopped hazelnuts in a small bowl. When truffle mixture has hardened, use the melon baller to scoop up 10 balls. Roll each ball in the hazelnuts to coat, then chill to set.
Make the jam. Cook the raspberries in a small pan over a medium heat for 5 minutes, or until soft and pulpy. Reduce the heat to low, add the sugar and heat gently until the sugar has dissolved. Then, increase the heat and simmer for about 5 minutes, or until the jam reaches 105°C on the sugar thermometer. Transfer to a bowl and refrigerate until needed.
Make the icing. Whisk the margarine by hand until light and fluffy. Sift in half the icing sugar and whisk to combine, then add the vanilla and remaining sugar and whisk again.
Put 2 tablespoons of the icing in a small bowl and add green food colouring until leaf-green. Place in the small piping bag fitted with the small star nozzle. Colour the remaining icing red and place in the medium piping bag fitted with the large star nozzle. Set both aside.
Whisk the cooled ganache in a stand mixer until light and fluffy.
To assemble, cover the bottom sponge with a thin layer of ganache, then a thin layer of jam. Repeat for the next tier, then place the last sponge, base upwards, on top. Spread the remaining ganache over the top and sides of the layered cake, then use an icing scraper to smooth the icing around the sides.
Pipe 3 or 4 large rosettes of red icing to make roses and use the green icing to pipe small rosettes representing leaves for each rose. Scatter dried raspberries over the cake and decorate as you wish with truffles, meringues and fresh raspberries.