200 gram dark chocolate, coarsely chopped, plus 200 g extra, melted
1 tablespoon instant coffee
2 cup firmly packed brown sugar
2 eggs, at room temperature
1 1/4 cup plain flour
1 1/4 cup self-raising flour
1/4 cup cocoa powder
300 gram white chocolate, chopped
1/2 cup thickened cream
Chocolate mud cake
Preheat oven to 150°C/130°C fan forced. Grease and line base and side of a 22cm (base diameter) round cake pan with baking paper.
Combine butter, dark chocolate, 1 cup hot water and coffee in a large saucepan over low heat. Cook, stirring for 5 minutes or until melted. Set aside for 5 minutes to cool.
Transfer to a bowl. Add sugar and eggs; whisk to combine.
Sift combined flours and cocoa powder over chocolate mixture; whisk to combine. Pour into prepared pan; level surface. Bake for 2 hours or until a skewer inserted at centre comes out clean.
Meanwhile, combine white chocolate and cream in a heatproof bowl over a saucepan of simmering water (don't let base of bowl touch the water). Stir until melted and smooth. Remove from heat. Remove bowl from pan. Cool for 5 minutes. Place in fridge, stirring occasionally, for 30 minutes or until mixture thickens.
Remove from oven. Cool completely in pan. Transfer to a serving plate.
Spread extra melted chocolate over a large piece of baking paper on a clean flat work surface. Stand for 5 minutes or until just beginning to set. Using a large sharp knife, pull blade across surface of chocolate to form a chocolate curl. Repeat to make more curls.
Spread ganache over top and sides of cooled cake. Decorate cake with chocolate curls. Serve.