Step 1

Preheat oven to 160°/140°C fan-forced. Grease a 6cm-deep, 22cm round cake pan. Line base and side with baking paper, allowing a 2cm overhang.

Step 2

Place butter, 1 cup cold water, milk, chocolate and sugar in a saucepan over medium heat. Cook, stirring occasionally, for 8 to 10 minutes or until smooth and combined. Set aside for 20 minutes to cool.

Step 3

Whisk flours and cocoa into chocolate mixture. Whisk in eggs until smooth and combined. Spoon mixture into prepared pan. Bake for 1 hour 40 minutes or until a skewer inserted in centre of cake comes out clean. Cool cake in pan.

Step 4

Make ganache: Place chocolate and cream in a microwave-safe bowl. Microwave on medium-high (75%) for 1 to 2 minutes, stirring with a metal spoon every 30 seconds, or until smooth. Refrigerate for 15 minutes or until thickened. 5 using a serrated knife, cut cake into 3 layers. Place base on a plate. Spread with 1/4 ganache. Top with layer of cake, then 1/3 remaining ganache. Top with cake top. Spread top and side of cake with remaining ganache. decorate with chocolate curls. Set aside for 1 hour. Serve.