How to cook
Prepare the starches according to packet directions.
In a cake form, put a little vanilla starch at the bottom, place a layer of biscuits, cocoa starch, another layer of biscuits, put some blackberry jam and then keep alternating between starch and biscuits.
Finish off with cocoa.
Put the cake form in the fridge and then invert it.
Decorate with melted chocolate.