Chocolate Buttermilk Cake

It's a well known fact that buttermilk instantly makes baked goods fluffy and light.  So I thought my next chocolate cake recipe should contain buttermilk to see if it would create a winner cake.  It definitely resulted in a fantastic cake which was fluffy...yet still dense. My friend's at school annouced it a "fluffy chocolate enjoyment." This may also be because the cake batter was made on oil (rather than butter) which means the cake will dry out slower and therefore keep better.   I think it even beat the original cake I posted from my Grandmother. Despite the praise, it was decided amongst us 15 or so school girls that Nigella Lawson's cake or the Women's Weekly cake are still the top contestants in this competition.  

Ingredients
2 cups flour
2 cups caster sugar
3/4 cup quality cocoa
2 tsp bicarbonate of soda
2 large eggs
1 tsp salt
1 cup buttermilk
1 cup vegetable oil
2 tsp vanilla extract
1 cup boiling water

Ingredients for Icing
1 1/2 cup icing sugar
2/3 cup quality cocoa
2 tbsp milk
2 tbsp butter, soft

Method
Preheat the oven to 150 degrees (fan-forced) and line a large round baking tin (This batter made a huge cake, plus an additional 4 cupcakes for my family, so prepare yourself for a large batter mix!)  Place all the ingredients in a mixing bowl, but ensure to sift the flour and cocoa beforehand.  Mix at medium speed until the ingredients are blended and smooth.  Pour into tin and bake for 1 hour - 1 hour and 20 minutes.  Test with a skewer.  Allow to cool in pan completely before turning out to wire rack.  To make the icing, beat all the ingredients in a bowl until smooth.  Ice cake using flicking motions to achieve this 'cloud like' icing texture.  Top with chocolate freckles, or homemade chocolate moulds (as pictured).