Unroll the puff pastry, cut in half lengthwise and remove from the paper. Place the puff pastry slices on 2 baking trays lined with baking paper. Let dough rest for 5-10 minutes.
Roll out puff pastry slices approx. 1 1/2-2 cm longer. Straighten the edges if necessary. Prick the dough several times with a fork, bake in a preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: see
manufacturer) bake for about 15 minutes until golden brown. Take out of the oven and let cool down.
Mix icing sugar, 1 tablespoon lemon juice and milk to a smooth thick icing. Put 2 tablespoons of icing in a small bowl. Stir in caramel and cover with foil. Spread a pastry sheet with icing, let it dry for about 1 hour.
After about 20 minutes, add the caramel icing as a dab. Cut the other pastry sheet into approx. 14 strips (approx. 3 x 12 cm).
Drain the peach halves, mash them. Mix mascarpone, sugar, 2 tablespoons lemon juice and vanillin sugar. Whip cream until stiff and fold in. Pour cream into a piping bag with a medium perforated spout.
Spread the cream over the strips. Pour peach puree on top. Cut the pastry sheet with the icing into approx. 14 strips as well and place on top. Serve immediately.