Beat the eggs and add the vanilla essence and glycerine. Mix the xanthum gum, baking powder and cocoa powder to the potato, rice and tapioca flour and mix really well.
Cream together the Pure spread and sugar and slowly add the egg mix. Add the flour blend and coconut milk and mix alternately until the mixture is smooth and combined.
Divide into two sandwich tins lined with baking parchment and bake in the centre of the preheated oven for 30 – 35 minutes or until a cake tester comes out clean after insertion.
To make the frosting, melt the chocolate carefully in a microwave or upon a pan of boiling water. Beat the icing sugar and Pure spread with an electric whisk for a good 5 minutes. Add the molten chocolate and stir well.
Spread the frosting in the centre of the cake and on the top and decorate.
I personally find this cake mixture gives enough for two really decent sized cakes. Each sandwich tin gives a cake that can be sliced in two. I usually freeze one and decorate the other. If however, you were wanting to really impress, you could make a 4-layer cake by slicing and using both cakes.