Preheat oven 175 degrees C (or 350 degrees F). Line the bottom of your cake tin with parchment paper and coat the sides of the tin using butter.
Next, in a large bowl combine the flour, sugars, baking powder, bicarbonate soda, cocoa powder and salt.
In a separate bowl combine the coffee and cold water until the coffee granules are gone. Set aside.
Make a round centre in the flour and pour in the coffee, buttermilk, eggs, vanilla extract and oil. Whisk the centre while gradually whisking the flour from the edges until the batter is smooth.
Pour the batter into the lined cake tin and bake for 40-45 minuets or until baked through.
Allow the cake to cool for 30 minutes.
Frost the cake and decorate with your favourite toppings.