01 - Preheat oven to 350°F. Line two baking sheets with parchment paper.
02 - Cream together softened butter and granulated sugar in a large bowl until light and fluffy.
03 - Mix in egg yolk and vanilla extract until fully combined.
04 - Add flour and salt; mix until a soft dough forms. Cover and refrigerate for 15 minutes.
05 - Combine almond flour, sugar, egg white, and almond extract in a medium bowl. Stir until smooth and thick.
06 - Divide chilled dough into 24 equal portions. Roll each into a ball, flatten into 2-inch rounds, and place 1/2 tsp almond filling in center. Fold and pinch dough around filling to seal, shaping into crescents.
07 - Gently press each crescent into sliced almonds so they adhere on top.
08 - Place cookies 1 inch apart on prepared baking sheets. Bake for 13-15 minutes until edges are golden brown.
09 - Cool on baking sheet for 5 minutes, then transfer to wire rack. Once completely cool, dust with powdered sugar.