Bake the puff pastry separately
22 minPreheat the oven to 200°C / 390°F. Unfold the puff pastry onto a parchment-lined baking sheet and prick it all over with a fork. Bake for 18 minutes, until deep golden and completely dry. Pastry that is still pale in the center will dissolve in the milk. Transfer it to a wire rack to cool.