preheat oven to 375°F. In a food processor, finely grind the almonds with almond flour, baking powder, and xylitol.

In a separate bowl, with an electric mixer on medium, beat whole egg and egg yolk, vanilla, and butter until well incorporated (mixture will not attain a smooth consistency). With a rubber spatula, fold in almond flour just until combined.

Form dough into 24 small balls and arrange on an ungreased baking sheet. Lightly flatten them with a fork to silver dollar size.

Bake 8 to 10 minutes, until set. Cool on baking sheets before transferring to a wire rack.