Method

1. Melt butter over a medium heat in a medium sized saucepan.
2. Add chopped chocolate, sugar, whisky and 1 1/2 cups water.
3. Stir over low heat until the chocolate is melted and sugar has dissolved.
4. Add flour and cocoa into warm chocolate mixture.
5. Add eggs and vanilla, and using a hand balloon whisk, whisk until combined. It will be thick and glossy.
6. Pour mixture into a greased and lined 20cm round cake tin.
7. Bake at 150 degrees celsius for 45 minutes. The cake may crack slightly on top, that's okay. When you press lightly on the top the cake it should spring back a little and feel firm. You want it to be cooked but still have moist crumbs clinging to a cake tester. If you need to cook it a little longer, cover it with foil and keep checking every 5-10 minutes.
8. Leave to cool in tin for 10 minutes then turn onto a wire rack to cool.
9. When it's completely cold, either dust with icing sugar or top with a Chocolate Gananche.
10. For the Chocolate Ganache, heat the cream in a saucepan over low to medium heat and bring to the boil.
11. Remove from the heat and add the finely chopped chocolate.
12. Leave to sit for a minute, then stir until the chocolate has melted and it's glossy and smooth.
13. Set aside to cool at room temperature, where it will thicken and turn from a pourable consistency to a spreadable one. If you are pressed for time, you can put it in the fridge, but just check on it, as it will go hard if you leave it in the fridge too long.
14. When it's the desired consistency, using a palette knife, spread the ganache evenly all over the cake.
15. This cake freezes really well, and will also last for a week in an airtight container in the fridge. As with most chocolate cakes, it's best eaten at room temperature, or if it's a few days old, reheat each slice in the microwave slightly before serving.