Instructions

1. Preheat oven to 180 C (350 F) standard / 160 C (320 F) fan-forced. Grease and line an 8-inch round cake pan with baking or parchment paper.
2. In a large mixing bowl, add gluten free flour, cocoa powder, sugars, baking powder, baking soda and salt. Whisk together.
3. In a separate mixing bowl, add vegetable oil, eggs, vanilla and buttermilk. Whisk together. Boil the kettle and pour out 1/2 cup of hot water.
4. Add the wet ingredients to the dry ingredients. Start to fold together, then slowly pour in the hot water, and continue to mix until all the ingredients are incorporated.
5. Transfer mixture into prepared cake tin and bake for approximately 35-40 minutes or until a skewer inserted comes out clean.
6. Leave for 10 minutes before gently removing cake from tin and leave to cool completely on a wire rack.
7. To make the frosting, place butter in a large mixing bowl and beat with an electric mixer on medium speed for a couple of minutes until pale and creamy.
8.  Add 1 cup of sugar and one tablespoon of milk and beat on low until the sugar is incorporated. Then, add the remaining sugar, cocoa powder and 1 tablespoon of milk, and beat on slow until the sugar is incorporated before turning up to medium for another minute or so.
9. If buttercream is too thick, add an extra tablespoon of milk. Generously frost top and sides of cake with chocolate buttercream.