01 - Preheat the oven to 350°F. Line two baking sheets with parchment paper.
02 - In a large bowl, cream together the butter and granulated sugar until light and fluffy using a hand mixer or stand mixer.
03 - Mix in the egg yolk and vanilla extract until fully incorporated.
04 - Add flour and salt to the mixture. Mix until a soft dough forms. Cover and refrigerate for 15 minutes.
05 - In a medium bowl, combine almond flour, sugar, egg white, and almond extract. Stir until smooth and thick consistency is achieved.
06 - Divide the chilled dough into 24 equal portions. Roll each into a ball, then flatten into a 2-inch round.
07 - Place 1/2 teaspoon of almond filling in the center of each round. Fold and pinch the dough around the filling to seal, shaping each into a crescent form.
08 - Gently press each crescent into the sliced almonds so they adhere evenly on top.
09 - Place cookies on the prepared baking sheets, spacing them about 1 inch apart to allow for slight spreading.
10 - Bake for 13-15 minutes, until edges are golden brown and centers are set.
11 - Cool on the baking sheet for 5 minutes, then transfer to a wire rack to cool completely.
12 - Once completely cool, lightly dust cookies with powdered sugar just before serving.