01 - Preheat oven to 350°F. Line two baking sheets with parchment paper.
02 - In a large bowl, beat butter and granulated sugar until light and fluffy.
03 - Mix in egg yolk and vanilla extract until fully combined.
04 - Add flour and salt; mix until 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, then flatten into a 2-inch round.
07 - Place 1/2 tsp almond filling in center of each round. Fold and pinch dough around filling, shaping into crescents.
08 - Gently press each crescent into sliced almonds so they adhere to the top.
09 - Place cookies on prepared baking sheets, spacing 1 inch apart.
10 - Bake for 13-15 minutes until edges are golden brown.
11 - Let cool on baking sheet for 5 minutes, then transfer to wire rack.
12 - Once completely cool, dust cookies lightly with powdered sugar.