Directions
1. Split a vanilla bean lengthwise and scrape seeds.
2. Heat milk, vanilla bean and seeds over medium heat until it begins to simmer.
3. In a bowl, whisk together sugar and cornstarch.
4. Whisk in egg yolks and continue whisking until light in colour.
5. Strain the milk to remove the vanilla bean.
6. Very slowly pour the hot milk into the eggs, whisking constantly.
7. Pour the mixture back into the pot.
8. While whisking, cook the mixture over medium heat until it thickens and before it starts to boil remove from heat.
9. Whisk into butter.
10. Transfer pastry cream to a bowl and cover the surface with plastic wrap and refrigerate at least 2 hours.
11. For the mille feuille, start by preheating an oven to 400°F.
12. Roll out the puff pastry until it is more than 12-inches long.
13. Brush a parchment-lined baking sheet with oil and place the puff pastry on top.
14. Brush with water and sprinkle with half the sugar.
15. Place another sheet of parchment on top followed by another baking sheet.
16. Bake for 15 minutes. Remove from oven.
17. Flip the pastry over and sprinkle with remaining sugar.
18. Bake for an additional 5 minutes.
19. Remove from oven and let cool.Slice into 3 even strips.
*To assemble, cover the first layer of pastry with half the pastry cream. Place another piece of pastry on top, followed by the remaining pastry cream. Place the last piece of pastry on top. Whisk together the icing sugar and cream. Frost the top of the pastry. Melt the chocolate in the microwave and place into a Ziploc bag with just the tip cut off. Pipe lines across the top. To make a marbled pattern, run a toothpick down the center lengthwise. Run the toothpick in the opposite direction halfway between both edges and the center. Chill until the frosting is set. Slice to serve.