Preheat oven to 200°C and line three 38x33cm trays with parchment.
Whisk egg whites and caster sugar to stiff peaks then set aside.
Whisk almonds, icing sugar, and eggs until pale and thick.
Fold in vanilla, sifted flour, meringue batches, and melted butter.
Spread batter on trays and bake for seven minutes at 200°C.
Simmer sugar and 250ml water for 10 minutes then add lavender extract.
Whisk egg yolks and lemon zest until thick for the buttercream.
Boil sugar, lemon juice, and 50ml water to 121°C without stirring.
Slowly whisk hot syrup into yolks then add butter, limoncello, and extracts.
Melt white chocolate into simmering cream then stir in lavender and butter.
Layer sponges with syrup, ganache, and buttercream then freeze to set.
Roll fondant and marzipan into pearl shapes and dust with pearlescent powder.
Glaze the frozen cake with melted ganache and return to freezer.
Mould a white chocolate soap bar using a greased cutter and decorate.
Assemble the cake with pearls, the chocolate soap, and chocolate lettering.