Crisp caramelized puff pastry layered with silky vanilla diplomat cream and finished with classic feathered fondant icing.
Ingredients
Puff pastry
500 g all-purpose flour
12 g fine sea salt
260 ml cold water
40 g unsalted butter, melted and cooled
350 g unsalted butter, cold (for laminating)
Diplomat cream (vanilla)
500 ml whole milk
5 g vanilla bean paste
120 g egg yolks
120 g granulated sugar
50 g cornstarch
50 g unsalted butter, room temperature
6 g powdered gelatin
30 ml cold water (for blooming gelatin)
250 ml heavy cream, chilled
20 g icing sugar
Icing and finish
300 g icing sugar
45 ml hot water
5 ml lemon juice
20 g light corn syrup
40 g dark chocolate (60–70% cacao)
5 ml neutral oil
30 g icing sugar (for caramelizing baked layers)
Steps
Make the puff pastry
Combine flour and salt in a large mixing bowl.
Pour in cold water and melted butter.
Mix with a spoon until shaggy.
Knead on a lightly floured surface until smooth, about 3 minutes.
Shape the dough into a 2 cm thick rectangle.
Wrap the dough tightly and chill for 30 minutes.
Place the cold laminating butter between two sheets of parchment.
Pound and roll the butter into a 15 x 15 cm even square.
Chill the butter square for 10 minutes.
Roll the dough into a 30 x 30 cm square.
Place the butter square centered on the dough at a 45° angle (diamond orientation).
Fold the four corners of dough over the butter to enclose it fully.
Pinch seams to seal the butter inside.
Roll the packet into a 20 x 60 cm rectangle.
Fold the top third down to the center.
Fold the bottom third up to complete a single turn (letter fold).
Rotate the dough 90 degrees.
Wrap the dough and chill for 30 minutes.
Roll the dough into a 20 x 60 cm rectangle.
Fold the top third down.
Fold the bottom third up to complete the second turn.
Rotate the dough 90 degrees.
Wrap the dough and chill for 30 minutes.
Roll the dough into a 20 x 60 cm rectangle.
Fold the top third down.
Fold the bottom third up to complete the third turn.
Rotate the dough 90 degrees.
Wrap the dough and chill for 30 minutes.
Roll the dough into a 20 x 60 cm rectangle.
Fold the top third down.
Fold the bottom third up to complete the fourth turn.
Rotate the dough 90 degrees.
Wrap the dough and chill for 30 minutes.
Roll the dough into a 20 x 60 cm rectangle.
Fold the top third down.
Fold the bottom third up to complete the fifth turn.
Wrap the dough and chill for 45 minutes.
Bake the pastry layers
Preheat the oven to 200°C.
Line two baking sheets with parchment.
Roll the dough to 3 mm thickness.
Cut three 30 x 20 cm rectangles.
Place the rectangles on the lined baking sheets.
Dock the pastry evenly with a fork.
Cover each rectangle with parchment.
Place a second baking sheet directly on top to weigh it down.
Bake for 20 minutes.
Remove the top sheets and parchment.
Dust each rectangle evenly with icing sugar (for caramelization).
Reduce the oven to 180°C.
Bake until deep golden and crisp, about 12–15 minutes.
Transfer the sheets to a rack and cool completely.
Trim each rectangle to clean 30 x 20 cm slabs using a serrated knife.
Cook the pastry cream base
Bloom the powdered gelatin in cold water for 5 minutes.
Add milk to a saucepan.
Add vanilla bean paste to the milk.
Heat the milk to a gentle simmer.
Combine egg yolks and granulated sugar in a bowl.
Whisk the yolks and sugar until pale.
Whisk in the cornstarch until smooth.
Pour a third of the hot milk into the yolk mixture while whisking.
Pour the tempered yolk mixture back into the saucepan.
Cook over medium heat while whisking constantly.
Boil the pastry cream for 30 seconds while whisking.
Remove the pan from the heat.
Stir in the bloomed gelatin until dissolved.
Whisk in the butter until glossy.
Spread the pastry cream in a shallow pan.
Cover the surface with plastic wrap.
Chill the pastry cream until fully cold, about 2 hours.
Make the diplomat cream
Whisk the chilled heavy cream with icing sugar to soft peaks.
Whisk the cold pastry cream until smooth.
Fold a third of the whipped cream into the pastry cream.
Fold in the remaining whipped cream until just combined.
Chill the diplomat cream for 30 minutes.
Glaze the top layer
Sift the icing sugar into a bowl.
Add hot water, lemon juice, and corn syrup to the sugar.
Whisk until thick, smooth, and pourable.
Melt the dark chocolate with neutral oil until fluid.
Place one pastry slab on a rack over a tray.
Spread a 2–3 mm layer of white icing over the slab.
Pipe parallel lines of melted chocolate across the width.
Drag a skewer perpendicular through the lines in alternating directions to feather.
Chill the glazed slab until the icing sets, about 15 minutes.
Assemble
Place one unglazed pastry slab on a board.
Transfer the diplomat cream to a piping bag with a 14–16 mm round tip.
Pipe an even layer of cream over the slab in tight parallel lines.
Place the second pastry slab on top of the cream.
Press gently to level the layer.
Pipe an even second layer of cream over the second slab.
Place the glazed slab on top, glaze side up.
Press very gently to set the layers.
Chill the assembled mille-feuille for 1 hour.
Portion
Heat a serrated knife under hot water.
Wipe the knife dry.
Trim 5 mm from each edge to square the slab.
Cut the slab into 12 bars measuring approximately 10 x 5 cm.
Wipe and reheat the knife between cuts.
Notes
Technique keys: Keep everything cold during lamination; rest the dough as directed to prevent butter smearing and to maximize lift. Baking under a sheet pan controls rise for flat, sliceable layers.
Filling choice: Classic versions use vanilla crème pâtissière; the diplomat cream here adds lightness and clean slices. Omit gelatin for a softer set and assemble closer to service.
Flavoring: Replace vanilla paste with 5 ml pure vanilla extract added after cooking the pastry cream.
Crispness: Caramelizing the pastry with icing sugar creates a moisture barrier and enhances crunch. Assemble within a few hours of serving for best texture.
Cutting: A hot, dry serrated knife minimizes cracking of the icing and pastry.
Variations: Swap in coffee icing (add 5 ml espresso to the white glaze) or raspberry jam under the top sheet. For a simpler finish, dust the top with icing sugar instead of fondant.
Cooksmith