1. Grease and base line an 8 inch round loose bottomed or spring sided cake tin. 2. Chop the marzipan and place in a saucepan with the sour cream, 100g of the chocolate (chopped and grated) and the butter. 3. Heat gently until the mixture is melted and smooth. Remove the pan from the heat and beat in the sugar, egg yolks, flours and liqueur. 4. Whisk the egg whites until stiff and fold carefully into the mixture. Spread about 4 tbsp of the mixture evenly over the bottom of the tin and place under a preheated hot grill, until the mixture is browned and firm to the touch. 5. Repeat this process until all the mixture is used up. This should make between 15 - 20 layers. 6. Allow to cool in the tin. Carefully remove the cake from the tin and remove the base paper. 7. Put the remaining chocolate and the double cream into a bowl over a pan of simmering water. 8. Stir until smooth, and then allow to cool until thick enough to spread over the cake in a swirling pattern. NOTES : Chef:Greg Robinson