400g/14oz dark chocolate, broken into chunks
25g/1oz cocoa powder
250g/9oz golden caster sugar
1 tbsp ground ginger
140g/5oz ground almonds
6 large eggs, separated
FOR THE ICING
100g/4oz butter, cubed
50g/2oz dark chocolate – use a bar broken into pieces, or chips
200g/7oz icing sugar, sifted
2 tbsp ground ginger
few chunks crystallised ginger, chopped into small pieces
Heat oven to 180C/160C fan/gas 4. Grease a 20 x 30cm cake tin, and line the base and sides with baking parchment. Melt the chocolate, cocoa, sugar and butter together in a saucepan over a very low heat. Once the chocolate and butter have melted and sugar dissolved, remove from the heat and stir in the ginger and almonds, followed by the egg yolks, one at a time.
Beat the egg whites to stiff peaks. Using a metal spoon, stir a couple of spoonfuls of the egg whites into the chocolate mixture to loosen before very gently folding in the rest.
Gently scrape into the tin. Bake for 30-35 mins until the top looks set and the centre doesn’t wobble too much. Sit the cake tin on a wire rack and leave to cool completely.
Once cool, make the icing. Put the butter, chocolate, cocoa, icing sugar, ground ginger and 4 tbsp water in a pan. Gently heat, stirring, until you have a smooth icing. Pour over the cake (still in its tin), leave for 1-2 mins to cool slightly, then scatter over the ginger. Cool completely (you can also store in the fridge if you bring out to room temperature about 20 mins before serving) before cutting into bars.