Sieve flour, cocoa and Bicarb into a bowl.
Melt Butter Sugar and Golden Syrup on a low heat in a saucepan. Do not allow to boil.
Once melted remove from the heat and pour the butter into the flour mixture.
Add the milk and with a wooden spoon beat all ingredients until a smooth batter consistency.
Lightly grease and line a 8 inch cake tin. Bake in a moderate oven (gas mark 4 or 180C) for 30 minutes. Or if you have two separate sandwich cake tins, divide the mixture between the two and bake a moderate oven (gas mark 4 or 180C) for 18-20 minutes, or until a skewer inserted into the centre of the cake comes out clean.
Once baked, remove and cool completely. If using a single cake tin cut into 2 layers.
Mix together the butter icing and add your liqueur (to your taste).
Spread butter icing on the bottom layer of the cake, using the top layer to complete the cake.