Decorated dessert biscuit

For the decor dough, start by softening the butter. For this you can gradually heat it in the microwave at low power.

Add the icing sugar and mix the whole with a whisk.

Sift the flour and unsweetened cocoa powder over it. Add the egg whites and mix everything.

We will use a 40 cm by 30 cm silicone baking sheet. Spread a quite thin layer of decor dough over the entire surface using a palette knife.

Using a notched triangle, draw parallel lines in the decor dough. Then place this silicone sheet on a baking sheet, then put everything in the freezer.

The remaining decor dough can be frozen for later use.

For the Joconde cookie, put the almond powder in a container, add the icing sugar and the flour. Break an egg then mix everything with a whisk.

Break the second egg, then whisk vigorously for 2 to 3 minutes. It will lighten and whithen.

Pour the egg whites into the bowl of the electric mixer with a bit of caster sugar, then start whisking.

When the egg whites form a firm peak, add the remaining caster sugar gradually.

Once the egg whites are firm, add them to the almond mixture and mix gently using a whisk or a spatula.

Take the baking sheet out of the freezer, then spread this Joconde cookie over the decor dough still frozen. Use a palette knife if possible and be regular.

Bake the decor cookie in an oven preheated to 210 ° C for about 10 minutes while monitoring the baking regularly.

Remove it from the oven and slide the decor cookie onto a wire rack to allow it to cool.

Finally, turn the decor cookie over onto a sheet of greaseproof paper, then gently remove the silicone sheet.