1In a bowl, add your dry ingredients: 300g of golden caster sugar, 150g of light brown sugar, 300g of plain flour, 100g of cocoa, 2 teaspoons of bicarbonate of soda, 1 1/2 teaspoons of baking powder, and 1/2 a teaspoon of salt. Whisk them together.
2In a jug, add 250ml of buttermilk, 2 teaspoons of vanilla, 5 eggs, and 200ml of vegetable oil. Whisk to combine.
3Slowly add the wet mixture into the dry mixture using a stand mixer or hand whisk until you get a glossy batter. This should take about 2 minutes.
4Spread the batter evenly among three 8-inch cake tins and bake at 180°C for 30 minutes.
5Once the cakes are cool, layer them with chocolate ganache. The ratio is double cream to dark chocolate, for example, 600ml of cream to 300g of dark chocolate. Make sure to chill the cake in the fridge for 30 minutes.
6Ice the outside of the cake with the remaining chocolate ganache.