Method
Prep:30min  ›  Ready in:30min 

1. To make the custard: In a small saucepan, heat milk until it begins to bubble. Drop in the vanilla pod, remove saucepan from heat, and set aside to cool until just warm. In a medium saucepan, stir together the flour, sugar, salt and egg yolks. Beat for a moment, then gradually whisk in warm milk. Simmer over medium-low heat until the custard thickens, stirring constantly with a wooden spoon to prevent sticking. Transfer custard to a bowl, and allow to cool, stirring from time to time.
2. Preheat oven to 200 degrees C. Roll out the puff pastry to about 1cm thick; it should be the same size as a baking tray. Place the pastry onto a lightly floured baking tray, and prick all over with a fork.
3. Bake in preheated oven for 20 or until golden brown. Remove from oven, and cool pastry on the baking tray.
4. When the pastry has cooled completely, transfer it from the tray to a hard surface, and cut lengthwise into three 10cm wide strips. Spread one strip thickly with custard. Place a second strip directly over the first; spread the top evenly with jam. Cover with the third strip, and dust with icing sugar. With a very sharp knife, cut into 8 rectangular portions.