Ingredients

• 2 sheets (approx. 10x10 inches each) Frozen Puff Pastry
• 4 Large Egg Yolks
• 0.5 cup (for cream) + 2 tbsp (for pastry) Granulated Sugar
• 0.25 cup All-purpose Flour
• 2 tbsp Cornstarch
• 2 cups Whole Milk
• 1 tsp Vanilla Extract
• 2 tbsp Unsalted Butter
• 0.5 cup (for glaze) Powdered Sugar
• 1 tbsp (for glaze, plus more as needed) Water
• 1 tbsp (for decoration) Unsweetened Cocoa Powder or Melted Chocolate

Instructions

1. 1

   **Prepare Pastry Cream (Crème Pâtissière)**: In a medium bowl, whisk together the egg yolks, 1/2 cup granulated sugar, all-purpose flour, and cornstarch until the mixture is smooth and pale.

2. 2

   **Heat Milk**: In a saucepan, heat the whole milk over medium heat until it just begins to simmer. Gradually whisk about half of the hot milk into the egg yolk mixture to temper it, then pour the tempered mixture back into the saucepan with the remaining milk.

3. 3

   **Thicken Cream**: Return the saucepan to medium heat and cook, whisking constantly, until the cream thickens significantly and comes to a boil. Remove from heat, stir in the vanilla extract and unsalted butter until fully incorporated.

4. 4

   **Chill Cream**: Transfer the pastry cream to a clean bowl, press plastic wrap directly onto the surface to prevent a skin from forming, and refrigerate for at least 2 hours, or until thoroughly chilled.

5. 5

   **Bake Puff Pastry**: Preheat oven to 400°F (200°C). Thaw and unroll the puff pastry sheets. Prick each sheet generously with a fork to prevent excessive puffing. Sprinkle lightly with 1 tablespoon of granulated sugar per sheet. Place each sheet between two sheets of parchment paper, then top with another baking sheet to keep them flat. Bake for 15-20 minutes, then remove the top baking sheet and parchment, and continue baking for another 5-10 minutes until golden brown and crisp. Let cool completely on a wire rack.

6. 6

   **Assemble Mille-feuille**: Once cooled, carefully trim the puff pastry sheets into three equal rectangles (approximately 4x10 inches each, depending on original sheet size). Whip the chilled pastry cream briefly to loosen it if needed.

7. 7

   **Layer**: Place one pastry rectangle on a serving plate. Spread an even, generous layer of pastry cream over it. Top with a second pastry rectangle, spread with another layer of cream, then finish with the third pastry rectangle.

8. 8

   **Decorate Glaze**: For the glaze, whisk the powdered sugar with 1-2 tablespoons of water until smooth and pourable. Spread evenly over the top pastry layer. While the glaze is still wet, pipe thin lines of melted chocolate or a cocoa powder mixture across the top. Drag a toothpick perpendicularly through the chocolate lines to create a classic feathered pattern.

9. 9

   **Chill and Serve**: Refrigerate the assembled mille-feuille for at least 30 minutes to allow the cream and glaze to set. Using a very sharp, serrated knife, slice carefully into individual portions and serve immediately.