Creating these Pistachio-Crusted Croissants with Rose-Petal Dust can be simple if you follow these straightforward steps:

1. Prepare the Puff Pastry: Preheat your oven to 400°F (200°C). Roll out the thawed puff pastry on a lightly floured surface into a rectangle. Cut the pastry into triangles.

2. Make the Pistachio Mixture: In a bowl, combine the finely chopped pistachios, granulated sugar, and dried rose petals. Mix well until evenly distributed.

3. Fill the Croissants: Take each triangle of puff pastry and place a spoonful of the pistachio mixture at the wide end. Roll the pastry towards the point to form a croissant shape.

4. Prepare for Baking: Place the rolled croissants on a baking sheet lined with parchment paper. In a small bowl, whisk together the egg and milk to create an egg wash. Brush the tops of the croissants with the egg wash for a golden finish.

5. Bake: Sprinkle the remaining pistachio mixture over the croissants for added crunch. Bake in the preheated oven for 25-30 minutes or until they are golden brown and flaky. Allow them to cool slightly before serving.