Apple buttercream cake

Ingredients for 1 servings:

• 3 eggs
• 1 pinch of salt
• 110 g sugar
• ½ vanilla pod(s)
• 110 g flour
• 110 g butter, liquid
• 50 g sugar
• 1 tsp vanilla sugar
• 3 tbsp Calvados
• 4 egg whites
• 60 g sugar
• 50 g hazelnuts, ground
• 50 g almond(s), ground
• 95 g powdered sugar
• 15 g flour
• 1 egg yolk
• 60 g sugar
• 60 ml milk
• 170 g butter, soft
• 1 tbsp kirsch, optional
• ½ vanilla pod(s)
• 50 ml apple juice
• 2 tbsp powdered sugar
• 100 g apple sauce, from the jar
• 30 g almond(s), flakes

Instructions

Working time approx. 1 hour; Total time approx. 1 hour

For the sponge cake: Separate the eggs. Beat the egg whites and salt until stiff peaks form, then add the sugar and scraped vanilla seeds and continue beating until the sugar has dissolved. Stir in the egg yolks. Sift the flour over the cake and add the lukewarm melted butter. Carefully fold in the flour and butter with a whisk and transfer the sponge cake to a springform pan (26 cm diameter) lined with baking paper. Bake in a preheated oven at 180°C, fan oven 160°C, gas mark 3 for about 15 to 20 minutes. Turn the sponge cake upside down in the pan and leave to cool on a wire rack. To soak the cake: Bring the sugar, 190 ml water, and vanilla sugar to a boil and stir until the sugar has dissolved. Allow to cool and then stir in the Calvados. For the nut meringue base: Beat the egg whites until stiff peaks form and then add the sugar. Continue beating until the sugar has dissolved. Mix the nuts, almonds, powdered sugar, and flour and lightly fold in with a whisk. Draw two circles (26 cm in diameter) on baking sheets lined with baking paper and spread half of the meringue mixture evenly into each. Bake the meringue bases one after the other in a preheated oven at 180 degrees Celsius, fan oven 160 degrees Celsius, gas mark 3 for about 20 minutes. Allow to cool. For the buttercream: Beat the egg yolks, sugar, and milk and heat gently or over a hot water bath while stirring until the cream thickens. Allow to cool while stirring. Beat the butter with the whisk of a hand mixer until light and fluffy. Gradually beat in the egg yolk mixture in small portions (otherwise the butter will curdle). Gradually beat in the kirsch, scraped vanilla seeds, apple juice, and powdered sugar. To assemble: Spread a meringue base with buttercream about 2 mm thick and chill for 15 minutes. Then spread the apple sauce on top. Using a long serrated knife, thinly slice off the top brown “skin” of the sponge cake to allow the sugar solution to penetrate more easily. Drizzle the sponge cake with half of the sugar solution and place the drizzled side on the apple sauce. Drizzle the remaining sugar solution over the sponge cake. Spread about 2 mm of buttercream over the soaked sponge cake and place the second meringue layer on top. Spread the remaining buttercream over the edge of the cake. Chill the cake. Toast the flaked almonds in a dry pan until golden brown, let them cool, and sprinkle them over the edge of the cake.