Preheat the oven to 180°C and line muffin tins with cases.
Beat butter and sugar until fluffy, then gradually add eggs and vanilla.
Sift flours, bicarbonate of soda, and cocoa into a large bowl.
Fold the flour mixture and buttermilk into the butter mixture until smooth.
Spoon batter into cases and bake for 20 minutes.
Cool the cupcakes completely on a wire rack.
Dissolve sugar and golden syrup in 60ml of water over gentle heat.
Boil the syrup until it reaches 115°C on a sugar thermometer.
Whisk egg whites to soft peaks and slowly stream in the hot syrup.
Whisk at high speed for 10 minutes until the icing is cool and thick.
Pipe a circle then a tall mound of icing onto each cupcake.
Decorate with chocolate strands to form ghost eyes.