Squeeze the lemon. Peel and grate the apple and sprinkle with lemon juice. Cut 4 mint leaves into small pieces. Pour 250 g cottage cheese in a bowl and add the elderberry syrup and the mint. Whip 125 ml cream and a sachet of vanilla sugar into the whipped cream and add this mixture gingerly to the cottage cheese. Put 4 Cantuccini cakes in a freezer bag and crush them with a rolling pin until they crumble. Cut four walnuts in half and caramelize them: heat 30 g sugar and 30 water in a saucepan and stir constantly until the mixture takes a honey colour. Slide the walnuts into the mixture and leave them to cool on a plate. Fill 4 jars with a layer of cream, then a layer of biscuits and a final layer of cream. Decorate with a mint leaf and two walnut halves for a refreshing sweet treat!