Prepare the Almond Meal: Place the peeled almonds (or almond flour) and sugar in a food processor. Grind until a fine meal is achieved. Be careful not to over-process to avoid overheating the almonds; pulse every 5 seconds or use the pulse mode.

Whip the Egg Whites: In a medium bowl, whip the egg whites with a pinch of salt until foamy. Add the bitter almond extract (if using) and a few drops of vanilla extract, being careful not to overpower the bitter almond flavor.

Form the Dough: Gradually incorporate the almond-sugar mixture into the whipped egg whites in two additions, folding gently until a sticky, thick dough forms.

Shape the Cookies: Wet your fingers with water, scoop small portions of the dough (about 30 g per cookie) and roll into 14 balls. Roll each ball in granulated white sugar to coat.

Decorate and Chill: Place the coated balls on a baking sheet lined with parchment paper. Press a whole almond into the center of each ball. Refrigerate the cookies for at least 2 hours to create a dry, crispy crust on the outside.

Bake: Preheat your oven to 160°C (320°F). Bake the cookies for about 20 minutes or until the edges are pale golden, but the centers remain soft when pressed.

Cool: Allow the cookies to cool slightly on the baking sheet for about 15 minutes before transferring them to a wire rack to cool completely.