Make a caramel with 100 g of sugar. When golden, add the butter, mix well, and finally add the thinly sliced apples. Pour the caramelized apple mixture into 4 plates/bowls in which the panna cotta will be served and let cool in the refrigerator. Heat milk, cream and sugar to 60°C and add the previously soaked and squeezed gelatin. Pour the lukewarm mixture into the bowls over the caramelized apples. Chill in the refrigerator and serve.