In a saucepan, heat the milk over medium heat until it’s warm but not boiling.
In a bowl, whisk together egg yolks, sugar, and cornstarch until smooth.
Slowly pour the warm milk into the egg mixture, whisking constantly.
Return the mixture to the saucepan and cook over medium heat, stirring continuously until it thickens.
Remove from heat, stir in vanilla extract and ground hazelnuts, then let it cool slightly.
Assemble the Puff Pastries:
Preheat the oven to 200°C (400°F).
Roll out the puff pastry sheet and cut it into squares or rectangles.
Spoon a generous amount of hazelnut custard onto the center of each square.
Fold or shape the pastries as desired (triangles, rectangles, or envelopes).
Brush with beaten egg for a golden finish.
Bake for 15–20 minutes or until puffed and golden brown.
Serve:
Allow pastries to cool slightly before serving.
Dust with powdered sugar if desired for an extra touch of sweetness.
Tips & Variations
