Preheat your oven to 180 Degrees C (350 F).
Prepare two baking trays by lining them with non-stick baking paper
Add the almond flour, sugar and sifted cocoa powder to a medium-size bowl. Use a whisk to thoroughly combine the ingredients.
Add the egg whites to a separate medium-size bowl.Using a fork or small whisk, whisk the egg whites for about a minute or until they are frothy and foamy. Do not whisk too long, you are not looking for soft peaks. Add the vanilla to the whites and whisk to combine.
Add the almond flour, sugar and cocoa and stir until they are well combined.
Use a small ice cream scoop to evenly distribute the mixture on the trays. Mine is about 3 ½ cm (1 ¼ inch) in diameter.Alternatively, use a teaspoon. The volume of the ice cream scoop is about 2 ½ level teaspoons. Roll into small balls. Place the cookie mixture onto the prepared trays allowing a little room between each so the heat can properly circulate, and they cook evenly. Top with a blanched almond half and gently flatten a little with flat fingertips. Bake the cookies for about 13 – 15 minutes, turning the trays around halfway to bake evenly.
Remove from the oven and leave on the trays for a few minutes.
Transfer the cookies to wire racks to cool completely. Store the cookies in an airtight container at room temperature.