French Vanilla Slices (Mille-feuilles) Recipe

In a small saucepan heat milk until small bubbles form. 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.

Preheat oven to 400 degrees F (200 degrees C). Roll out the puff pastry into a single sheet about 1/2 inch thick; it should be the same size as a 17x14 inch baking sheet. Place the pastry onto the baking sheet and prick all over with a fork.

Bake in preheated oven for 28 minutes. Remove from oven and cool pastry on the baking sheet.

When the pastry has cooled completely transfer it from the baking sheet to a hard surface and cut lengthwise into three 4 to 5 inches 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 confectioners' sugar. With a very sharp knife cut into 8 rectangular portions.