Laminate the puff pastry or puff pastry trimmings on setting 2.
Prick and cut out Ø21-cm circles.
Place on baking sheets lined with baking paper that has been brushed with water to moisten it lightly.
Place the baking trays in the refrigerator for 1 to 2 hours.
Prepare a traditional choux pastry.
Using a piping bag fitted with a #9 tip, pipe out 18 medium-sized choux puffs for each puff pastry circle.
Preheat the oven to 230°C.
Turn the oven off, place the choux puffs in the oven and leave them for 15 minutes.
Turn the oven back on to 170°C and continue baking for approximately 20 minutes.
Let cool on a cooling rack.
Using a piping bag fitted with a #9 tip, pipe the Saint-Honoré base in a crown shape 1 cm from the edges of the puff pastry bases.
Then, pressing on the pastry bag, pipe out a fine, light spiral inside. Bake at 170°C for 40 minutes.
Let cool on a cooling rack.
Stir the pastry cream using the whisk attachment of the stand mixer.
Scrape the sides of the bowl down well.
Add the hazelnut paste, then manually fold in the whipped cream.
Prepare a syrup with the water, sugar and trimoline, then pour over the hazelnuts.
Caramelize in a 220°C oven.
5 minutes after putting the hazelnuts in the oven, stir them with a greased triangular spatula, repeat after another 4 minutes and then every 3 minutes until evenly caramelized.
Transfer to a lightly oiled marble work surface.
Grind the cooled hazelnuts with the fleur de sel to obtain a praliné.
Store in airtight containers.
Whip the cream with the sugar in a chilled bowl using the whisk attachment.
Bring the syrup to the boil, skim off any impurities and let cool.
At 170°C, transfer half of the light caramel to another saucepan.
Add the bronze powder.
The other half of the syrup will darken naturally.
Pierce a hole in the bottom of the choux puffs to fill with hazelnut diplomat cream.
Dip the 18 choux puffs in the boiled sugar syrup and place them sugar side down to cool in Ø4.5-cm hemispherical silicone moulds.
Then, dip them one by one in the boiled sugar syrup (half in each colour), and place side by side on the crown of choux pastry before turning the Saint-Honoré upside down to cool down.
Remove any excess sugar if necessary.
Fill the Saint-Honoré with hazelnut diplomat cream using a piping bag.
Pipe out a spiral of hazelnut praliné in the centre and cover with chopped caramelized hazelnuts.
On the surface, pipe out the chantilly cream using a piping bag.
Decorate with hazelnuts, according to taste.