For the Plundertascherl, wash the peaches, remove the pits and cut into small wedges.
Melt 2 tablespoons of sugar in a saucepan and caramelize the peaches.
Mix the mascarpone with the yolk and the remaining sugar until smooth.
Chop the chocolate and stir it in as well. Cut 8 rectangles from the puff pastry and cover each with a heap of peaches and a heap of cream.
Brush the edges with egg white and fold into pockets. Preheat the oven to 180 degrees and place the patties on a baking tray lined with baking paper.
Bake for about 15-20 minutes on the middle shelf until they are lightly golden brown. Let the pastries cool and sprinkle with sugar.