Break up the chocolate

• Break the chocolate into small bits so it melts evenly.
• Set half aside for the icing and keep the rest for the sauce.

Warm the cream

• Gently warm the cream in a saucepan until hot but not boiling.

Make the chocolate sauce

• Pour the warmed cream over the chocolate bits.
• Let it sit for a moment, then stir until smooth and glossy.

Make the chocolate icing

• Beat the softened butter with the icing sugar and cocoa powder until smooth.
• Add a little of the cooled chocolate mixture and whisk until spreadable.

Ice the cake

• Spread the icing over the cooled cake, smoothing the top and sides.
• Drizzle the chocolate sauce over the top before serving.