Shells:
In a bowl, mix together the powdered sugar and almond powder with 45 ml of egg whites and add the coloring.

Pour the sugar into a saucepan, add about 35 ml of water, and heat.
Place the thermometer probe in the sugar syrup and set the alarm to 121 C (250 F).

Once the syrup is boiling, start beating the remaining 45 ml of egg whites with an electric mixer.
Once the syrup reaches 121 C (250 F), remove the saucepan from the heat. Without stopping the mixer, slowly pour the syrup over the egg whites.
Continue beating the meringue until it is lukewarm and the perfect consistency: the meringue should hold its shape on the whisk in a “bird’s beak” shape.

Now comes the delicate moment of the final mixture, which consists of folding the mixture until it reaches the perfect consistency: the surface of the beaten mixture should be smooth and shiny, but not too liquid.
To do this, pour the meringue over the mixture of powdered sugar, almond powder, and egg whites, and gently fold in with a silicone spatula.
Always bring the two masses back to the center until they are fully combined. Repeat this movement until the right consistency is achieved.

Preheat the oven to 150 C (300 F).
On a baking sheet lined with parchment paper, pipe small circles of about 4.5 cm (1 and 3/4 in) in diameter.
Sprinkle with crumbled maple syrup. Let it sit until the surface is slightly dried.
Bake for 12 minutes and let cool completely.

Creamy:
Soak the gelatin sheet in a large volume of cold water.
Make a dry caramel: heat a saucepan, pour in the sugar, and stir until a caramel is obtained (the darker the color, the more pronounced and less sweet the caramel flavor will be).
Remove from heat, slowly pour in the cold cream while stirring constantly, then bring back to a boil.
Pour the boiling mixture over the egg yolk while stirring vigorously.
Add the drained gelatin. Let it cool down.
Incorporate the butter. Mix, add the fleur de sel, and store in a container in the refrigerator.

Assembly: Remove half of the shells and turn them over on a clean plate.
Generously fill with creamy caramel using a piping bag, then close with the remaining shells, taking care to always assemble shells of the same size.

Store the macarons in an airtight container and refrigerate for at least 24 hours to allow them to mature.
Take them out 15 to 30 minutes before serving.