01 -
Gently heat the milk, but keep it from boiling. Whisk together the yolks, sugar, flour, and vanilla till smooth and fluffy. Add the warm milk slowly while mixing. Stir constantly as it cooks over medium heat until it thickens up. Chill it in the fridge for at least an hour.
02 -
Preheat the oven to 400°F. Dust your surface lightly with sugar, then roll out the pastry to create a 9x12 inch rectangle. Slice it into 12 one-inch-wide strips.
03 -
Wrap each pastry strip around a mold, keeping a slight overlap. Place them seam-down on a parchment-covered baking tray.
04 -
Stir one tablespoon of water into the egg, then lightly coat the pastry with the mixture. Be sure you don’t let the egg touch the molds.
05 -
Pop the tray into the oven at 400°F and bake for 15–20 minutes, or until golden and crispy. Let them cool before carefully removing the molds.
06 -
Fill the cooled pastry horns with the chilled custard. Dust a bit of powdered sugar over the top, then serve.