In a bowl, mix the biscuit base ingredients together with a spatula for a few minutes.

For the meringue, heat the sugar and water to 121 °C in a saucepan. Remove from the heat. Whisk the egg whites. As you continue whisking, very gently pour the cooked sugar into the whites.

Incorporate the meringue into the base mixture; no particular care is needed. Pipe out half-macarons using a piping bag fitted with a no. 7 nozzle onto some baking parchment. Leave to rest for 45 minutes. Lay the sheet on an over tray or preferable a cast iron roasting tray. Preheat the oven to 240 °C for 15 minutes. Bake for 10 minutes at 180 °C. Remove from the oven. Slightly dampen the underside of the paper with cold water, then detach the macarons. Set them upside down on a sheet of baking parchment placed on a rack.

For the ganache, bring the whipping cream to the boil in a saucepan. Remove from the heat. Pour the boiling whipping cream over the chocolate (chopped beforehand) and stir. Incorporate the butter. Pour the ganache into a stainless steel tray. Leave to cool. Refrigerate for about 30 minutes.

To assemble, use a piping bag with a no. 7 nozzle to top half the macaron shells. Complete using the other half of the shells. Your macarons are ready to enjoy. The macarons will keep for a maximum of 3 days in an airtight container.