01 - Preheat the oven to 350°F. Line two baking sheets with parchment paper and set aside.
02 - In a large bowl, beat the softened butter and granulated sugar together until light and fluffy, approximately 2 to 3 minutes.
03 - Mix in the egg yolk and vanilla extract until fully incorporated into the butter mixture.
04 - Add the all-purpose flour and salt to the bowl. Mix until a soft dough forms, being careful not to overmix. Cover the dough and refrigerate for 15 minutes.
05 - While the dough chills, combine the almond flour, sugar, egg white, and almond extract in a medium bowl. Stir until the mixture is smooth and thick.
06 - Divide the chilled dough into 24 equal portions. Roll each portion into a ball, then flatten into a 2-inch round disc.
07 - Place 1/2 teaspoon of almond filling in the center of each dough round. Fold and pinch the dough around the filling to seal, shaping each into a crescent form.
08 - Gently press the top of each crescent into the sliced almonds, ensuring they adhere evenly to the surface.
09 - Place the prepared cookies on the lined baking sheets, spacing them approximately 1 inch apart to allow for even baking.
10 - Bake for 13 to 15 minutes, or until the edges are golden brown and the bottoms are lightly browned.
11 - Let the cookies rest on the baking sheet for 5 minutes, then transfer to a wire rack to cool completely.
12 - Once fully cooled, lightly dust the cookies with powdered sugar just before serving.