Soy lecithin is needed to improve the texture of the ganache. It should produce a stable emulsion. But overall, it’s an optional ingredient!
For the ganache:
270 g sugar-free dark chocolate
12g coconut oil
10g refined sunflower oil
2g of liquid soya lecithin
For the frosting:
60 g dark chocolate
15 g grape seed oil or other unscented and refined oil
For the chocolate sponge cake:
165 g chocolate soy milk
80 g dark chocolate
50 g coconut butter
95g brown sugar
95 g rice flour
20 g ground flaxseed
2 g instant coffee
15 g cocoa powder
4 g of baking powder
1 g salt
Step by step recipe
For the sponge cake, pour 40 ml of drinking water over the flaxseeds. Leave to thicken.
Melt the chocolate and butter mixture in a water bath or in a microwave in several batches for 30 seconds. Add to the mixed dry ingredients. Add the flaxseed and soy milk. Stir until smooth.
Place two 16 cm diameter pastry rings on a baking tray lined with a silicone mat. Spread the batter over them. Bake in a preheated 180°C oven for 25-30 minutes. Leave to cool completely.
For the ganache, melt the mixture of chocolate and all the butter in a water bath. Keep the heat to a minimum and the temperature of the mixture to 50°C. Add the lecithin. Stir to mix. Pipe in 300 ml of drinking water (20 °C), whisking the ganache with an immersion blender. Mix until homogeneous. Remove from heat.
Transfer the ganache to a large food processor, be sure to have a flat bottom, and cover with cling film. Place in the refrigerator for at least 3 hours.
To assemble the cake, put a silicone mat or baking paper on a cutting board, place a 16 cm diameter pastry ring lined with acetate film. Place one biscuit in the ring and a layer of ganache on top. Repeat, leaving the ganache for the sides and decoration. Place in the freezer for 30 minutes.
For the icing, melt chocolate in a water bath. Keep the heat to a minimum and the temperature of the mixture to 50 °C. Stir in the butter and remove from heat.
Pour the warm frosting onto the cake. Allow it to set, remove the ring from the cake. Spoon the ganache over the sides. Decorate the cake by depositing the remaining ganache from a pastry bag. Place the cake in the refrigerator until serving.