In a stand mixer, add the pistachio paste, butter and sugar. Blend until combined then add the double cream and continue to mix well until light and fluffy. Slowly add the egg yolks a few at a time and mix between additions until all well incorporated.

Sift the flour and cornflour into the mixture and fold in with a metal spoon until combined. Set aside.

In a clean bowl, whisk the egg whites until soft peaks form. Add the egg whites to the cake mixture and fold in with the metal spoon until incorporated trying to keep as much air in as possible.

In a small pan melt the lemon marmalade over a low heat and keep warm. In the glass bowl over simmering water add 150g of the white chocolate with 25g butter and melt over low heat, add the drops of rose water (you can adjust this amount to your taste but do be careful as rosewater can be a delicate flavour if used lightly but overpowering if too much useagain keep warm.

To make up the cake, preheat the grill to 190Butter and line a 23cm springform pan. Start by adding a thin layer of the batter in the pan, making sure it spreads all over the pan. Place under the grill for 3-4 minutes until golden and set on top. Remove from the oven. Using a pastry brush, brush a layer of the melted marmalade over the top of the first cake layer. Add another thin layer of batter and spread evenly and then place under the grill again for 3-4 minutes until golden. Brush a layer of the melted white chocolate, taking care not to tear the cake layer. Continue this way with layering with batter, lemon, batter, white chocolate, finishing with a layer of melted marmalade. When the batter is used up and all layers grilled, run a sharp knife around the edges as the marmalade will get sticky once cooled. Leave the cake to cool completely on a wire rack.

Once the cake is cooled, remove from the pan and place on a cake plate. To make the icing, in a small bowl, melt the white chocolate in the microwave slowly so as not to burn. Mix well and add the yogurt to loosen the chocolate. Add the suggested amount of rose water to your taste and mix. To decorate the cake, spread the melted chocolate around the edges of the cake and immediately press the crushed pistachios onto it. You can finish by adding a few more pistachios to the top.