Defrost the puff pastry slices. Put sugar and 2 tablespoons of water in a pan and caramelise while stirring until golden brown. Pour a fruit base mould (30 cm Ø) with the caramel and distribute evenly.
Wash the apples, prick out the core. Cut apples into 1/2 cm thick slices. Cover the caramel with the slices. Roll out the puff pastry slightly larger than the tin and place it over the apples. Press down the edge.
Bake in the preheated oven (electric oven: 225 °C/ gas: level 4) for approx. 25 minutes. Remove and immediately turn out onto a cake plate. Heat up the apricot jam and spread on the apples.
Roast the hazelnut leaves in a dry pan until golden brown and sprinkle over the cake immediately. Serve lukewarm with vanilla ice cream sauce. Makes about 12 pieces.