Pantxineta (Basque Almond Custard Tart)

Instructions

1. Make the cream: whisk the yolks, sugar and cornstarch in a bowl. Heat the milk with the vanilla until steaming, then slowly whisk it into the yolk mixture.
2. Return everything to the saucepan and cook over medium heat, whisking constantly, until it thickens and bubbles for 1 full minute. The custard is then cooked past 160 F (71 C).
3. Stir in half of the sliced almonds, scrape the cream into a shallow dish, press plastic wrap on the surface and chill at least 2 hours until firm.
4. Heat the oven to 400 F (200 C). Roll one puff pastry sheet to a rectangle about 10 x 12 inches and place it on a parchment-lined baking sheet.
5. Spoon the cold cream onto the sheet, spreading it to leave a 1-inch border on every side. Brush the border with beaten egg.
6. Roll the second sheet slightly larger, lay it over the cream and press the edges to seal. Crimp with a fork and cut 3 small steam slits in the top.
7. Brush the top with egg, scatter with the remaining almonds and bake 20 to 25 minutes, until puffed and deep golden.
8. Cool on the sheet for at least 30 minutes, dust with powdered sugar and cut with a serrated knife. Serve the same day.