Napoleon Cake (VIDEO)

Making the pastry cream filling and frosting

In a large enough bowl with the help of a Hand whisk, whisk together sugar and egg yolk until slightly fluffy for about 1-2 minutes. Mix in corn starch, flour, and vanilla until thoroughly incorporated and have a smooth paste.

Bring milk to simmer in a saucepan on medium heat then remove it from the stove. Pour the warm milk over the egg yolk mixture slowly while whisking vigorously with a Hand whisk.

Pour the mixture back into the saucepan and cook on medium heat for a few minutes until it thickens. Concretely it is approximately 1 min after the first boil. It might get lumpy first, but don't worry just keep whisking and the cream will get smooth and glossy.

Add in room temperature soft butter and mix with a rubber spatula until completely incorporated. It is worth to add the butter in 3 stages and mix well after each addition.

Place the cream into a shallow bowl and cover the entire surface with plastic wrap to avoid skin forming on top. Let it come to room temperature.

Before making the mousseline cream, take out about 1/2 of the pastry cream - this will be used as a filling and will go inside the puff pastry layers.

The other half of the pastry cream will be used as a base for the mousseline cream to frost the cake. Prepare the mousseline cream by whipping room temp butter first for 1-2 minutes. Start adding in the remaining half room temp pastry cream in 4 stages until the cream reaches a stable yet fluffy texture.

Do not over whip the mixture as it can become runny or can curdle. The cream might be on the soft side at this point due to the room temp butter used so place it back into the fridge for an hour to chill before using it.

Prepare the rough puff pastry dough

Measure water and vinegar, mix them in a small bowl and place them into the freezer for 10 minutes

Cut butter into small chunks and pop them into the freezer for 10 minutes

Mix high protein content flour with salt in a large bowl

Add the cold butter chunks into the flour and toss the mixture with your fingers until all pieces of butter are separated and completely coated in flour. Work as quickly as possible

Using a rubber spatula, start adding the water-vinegar mixture to the flour slowly. Be mindful of the water, you might not need all of it, stop adding water as soon as the dough is moist enough but you do not want to make it wet. Add just enough water so that all of the dry dough pieces and flour bits at the bottom of the bowl become incorporated.

Once water is added, gently knead the dough for 10-20 seconds just until it comes together. You should have smaller and bigger butter chunks left in the dough. Do not overwork it.

Wrap the dough into a plastic wrap and refrigerate for one hour

Lamination process

Use Silicone baking mat to make the rolling and folding easier. Use as little extra flour as possible and work as quickly as possible.

Prepare a 6-fold rough puff pastry; Roll the dough into 25x45cm / 10x18inch, fold the top third into the middle, then fold the bottom third into the middle. Now you will get an envelope shape that has an "open edge" on the top and a "closed edge" on the bottom. Rotate by 90 degrees to the right so you will get the "open edge" on the right and the "closed edge" on left.

Your first fold is done, repeat it 6x. Rest the dough for 30-60 minutes either in between each fold (if your kitchen is warm) or in between 2 folds. Do not make more than 2 folds at once without resting the dough.

After the 6th fold, refrigerate the rough puff pastry dough for 1 hour before using it

Baking

Pre-heat oven to 190C / 374F (no fan)

Divide the dough into 9. Roll out each into a thin circle. Using a template and knife, cut out 16cm / 6inch circle of the dough and keep the trimmings - we will bake these too and use them to decorate the cake.

The pastry sheet circles will be baked in between two baking trays so they will puff up more evenly. Cover a large tray with parchment paper, place 2-3 round puff pastry sheets on top then poke small holes in them with a fork all around the surface. Cover the dough with another layer of parchment paper and place another large tray on top.

Bake the pastry at 190C / 374F for 30 min in between the two trays then continue with the rest. Let them come to room temperature before assembling the cake

Lastly, bake the trimmings at 190C / 374F for 15-20 minutes or until golden brown. Let them come to room temperature, then using a food processor or a ziplock bag and rolling pin, crush the baked trimmings into sand like consistency. This will be used to decorate the cake.

Assemble the Napoleon Cake

Once you have the 9 puff pastry layers, the pastry cream filling, the mousseline cream frosting, and the puff pastry crumbs ready, it is time to assemble the Napoleon Cake.

Start building up the cake from bottom to top allocating an equal amount of pastry cream in between the 9 layers (use a scale). Spread the pastry cream on top of a puff pastry circle and continue until the last layer is on top.

Chill the cake for 30 minutes before frosting the outer part with the mousseline cream. Leave some cream for decoration.

Chill the cake again for 30 minutes, then distrubute the crushed puff pastry crumbs all around the cake.

Lastly, pipe some decoration on top according to your liking.

Chill the cake for at least 24 hours for the layers to soften. The filling will nicely moisten the puff pastry layers making the cake super creamy.

Store the cake refrigerated and serve within 2-3 days.