This Portuguese cake actually originates from the 16th century. The monasteries would use egg whites to clarify wine or stiffen the nun's habits, and cakes like these were developed to use the remaining yolks. Waste not want not. However, as this cake is essentially a frangipane and I don't think many nun's will be using my books as a housekeeping guide, I use the entire egg as to not waste the white.

Method: 

• Preheat the oven to 170°C (fan) and line an 20cm (8-inch) springform sandwich tin with greaseproof paper.
• In a small saucepan melt the butter with the rosemary (if using). Pop to one side to cool.
• Separate the eggs, in a small bowl whisk the egg yolks and 100g of the sugar until pale and creamy. Then in a separate bowl whisk the egg whites with the remaining 25g of sugar until soft peaks form. Fold the whites into the yolks followed with the almonds and the melted butter.
• Pour the mixture into the prepared tin and bake for 25 minutes. Meanwhile, for the syrup combine the orange juice, amaretto and caster sugar in a small saucepan. Over low heat, stir constantly until the sugar has completely dissolved.
• Once the cake has baked, remove from the oven and use a tooth pick or pairing knife to poke 30 or so holes across the surface of the cake, going no more than half the depth. Pour the warm syrup over the cake to completely water-log it and allow it to cool completely in the tin.
• Once cooled, dust generously with icing sugar and scatter over a few flaked almonds.
• If making the whipped lemon and white chocolate ganache: finely chop the chocolate and place it in a heatproof bowl. Add the lemon zest and Juice. Heat the cream in a small saucepan over medium heat until wisps of steam appear on the surface, then pour it over the chocolate. Leave to sit for 1 minute before whisking into a smooth, glossy ganache. Chill until thickened.

  Using a stand mixer or electric hand whisk, whisk the ganache until fluffy and transfer it to a piping big fitted with your preferred nozzle. Pipe six rosettes on the top of the cake and garnish with a sprig of rosemary.