Steps
1. Preheat the oven to 180°C (350°F).
2. In a food processor, pulse pistachios until finely ground. Combine with flour and powdered sugar.
3. Add cold butter cubes and pulse until mixture resembles coarse crumbs.
4. Add egg yolk and rose water, pulse briefly to form a dough.
5. Press dough into a 12cm tart tin evenly. Chill for 15 minutes.
6. Bake crust for 15 minutes or until lightly golden. Let cool.
7. For custard: whisk egg, sugar, and cornstarch until smooth.
8. Heat milk and vanilla in a saucepan until just simmering.
9. Slowly pour hot milk into egg mixture, whisking constantly.
10. Return mixture to saucepan and cook over low heat, stirring until thickened.
11. Pour custard into cooled tart shell and smooth surface.
12. Refrigerate tart for 1 hour to set.
13. Before serving, arrange fresh raspberries evenly on custard.
14. Garnish with edible rose petals gently placed on top.
15. Serve on a white ceramic plate with a golden fork, ideal for a light summer afternoon.