Wash and halve the apples and remove the core. Cut apples into slices. Steam in hot lemon juice for two minutes. Season with sugar and cinnamon, let cool. Take the fresh dough out of the tin, unroll it and separate it into triangles.
Place on a baking tray lined with baking paper. Cover with apple pieces and roll up into croissants. Coat with condensed milk and bake in a preheated oven (electric range: 200 ° C/ gas: level 3) for twelve to 15 minutes.
Then let it cool down a little. Stir icing sugar and apple juice until smooth and spread a thin layer on the croissants. Serve sprinkled with ground pistachios.