1. Place all ingredients in mixing bowl except for the chocolate and beat with a wooden spoon until well mixed (2 - 3 minutes). Divide mixture into two and add melted dark chocolate to one half and white chocolate to the other.
2. Place alternate spoonfuls of mixture into a greased and bottom-lined 20cm (8 inch) cake tin, and gently swirl through mixture with a skewer.
3. Bake in middle of a pre-heated oven 170ºC, 160ºC fan, Gas mark 3 for 50-60 minutes. Turn out, remove paper and cool.
4. To make icing, place sugar, cream and salt in a saucepan and heat until sugar dissolves and then bubble for 4-5 minutes not stirring. Allow to cool for 10 mins and then beat in Stork. Chill in refrigerator until firm.
5. Split cake and sandwich together with half the icing. Melt chocolate and double cream together and then chill until a spreading consistency. Spread over the top and sides of the cake. Chill remaining ganache till firm.
6. Form the remaining icing and ganache into truffles and roll in either cocoa powder or popping candy. Use to decorate the top of the cake. Sprinkle with salt crystals if preferred.
Recipe courtesy of Stork
For more information, visit Bake with Stork