Preheat the oven to 160℃, grease and line a 18 cm springform tin with baking paper.

Add the buttermilk, vegetable oil, 2 eggs, soft brown sugar and the golden caster sugar into a large mixing bowl.

Use a whisk to mix it all together until well combined.

Sift in the flour, cocoa and baking powder. Use the whisk to mix until well combined.

Add the hot coffee. This doesn't flavour the cake with coffee but rather intensifies the chocolate. Whisk until well combined.

Pour the mixture into the baking tin.

Bake in the oven for 50 minutes.

Leave it to cool in the tin for about ten minutes before transferring it to a wire rack to cool completely.

To make the ganache, chop the chocolate into small chunks and place it into a mixing bowl.

Heat the double cream and golden caster sugar over a medium heat until almost boiling, but don't let it boil.

Pour the hot cream over the chocolate and beat with a whisk until silky smooth.

Leave it to cool for a few minutes, then pour it over the top of the cake. Spread it across the top and let it drop down the sides of the cake. You may want to lay a piece of baking paper underneath the wire rack to catch any bits of ganache that dribble through.

Leave it to cool completely, it will start to set. You can speed it up by leaving it in the fridge, but this is not essential.

Garnish with extra chopped chocolate.