Sift the almond flour and powdered sugar together.
Whip the egg whites until foamy, then gradually add the sugar in three parts to make a meringue.
Gently fold the almond flour and powdered sugar mixture into the meringue.
Transfer the batter to a piping bag and pipe out round shapes onto a baking pan.
Let the piped batter dry at room temperature for 10–20 minutes.
Bake in a preheated oven at 170°C (338°F) for 10–13 minutes.
After cooling, sandwich with filling (ganache, cream, etc.) in between the shells.