Step 1: Preheat your oven to 350°F (175°C) and line baking sheets with parchment paper.
Step 2: In a large bowl, cream together the softened unsalted butter and granulated sugar using an electric mixer until light and fluffy.
Step 3: Beat in the egg yolk and vanilla extract until well combined.
Step 4: In a separate medium bowl, whisk together the almond flour, all-purpose flour, baking powder, and salt.
Step 5: Gradually add the dry ingredients to the wet ingredients, mixing on low speed until just combined. Do not overmix.
Step 6: If the dough is too sticky, chill it in the refrigerator for 15-20 minutes.
Step 7: Scoop spoonfuls of dough (about 1 tablespoon each) and roll them into small balls.
Step 8: Gently flatten each ball with the palm of your hand or the bottom of a glass. Press a whole blanched almond into the center of each cookie if desired.
Step 9: Place the flattened dough balls about 2 inches apart on the prepared baking sheets.
Step 10: Bake for 10-12 minutes, or until the edges are golden brown and the centers are set.
Step 11: Let the cookies cool on the baking sheets for 5 minutes before transferring them to a wire rack to cool completely.
Step 12: Once completely cooled, store in an airtight container at room temperature.