How to Make It
Whisk together the flour, salt, and baking powder in a bowl.
Beat the butter, 1/2 cup of the sugar, and the finely ground anise seeds in a bowl with an electric mixer on medium-high until light and fluffy, 2 to 3 minutes. Beat in the whole egg and the egg yolk, one at a time, scraping down the sides of the bowl as necessary. Reduce mixer speed to low and gradually add the flour mixture, mixing until just combined. Shape into 2 1-inch-thick disks, wrap in plastic wrap, and refrigerate for at least 2 hours and up to 3 days.
Meanwhile, combine the remaining tablespoon of sugar, the remaining teaspoon of whole anise seeds, and 1/2 teaspoon of the egg white in a bowl. Let sit at room temperature to dry.
Heat oven to 350° F. Line 2 baking sheets with parchment.
Roll the dough 1/4 inch thick on a floured surface. Using a lightly floured 2-inch cookie cutter, cut the dough into shapes, flouring the cutters and rerolling the scraps as necessary.
Place the cookies 1 inch apart on the baking sheets. Sprinkle with the anise seed mixture, dividing evenly. Bake, rotating the sheets halfway through, until dry around the edges, 12 to 14 minutes. Let cool slightly on the baking sheets, then transfer to a wire rack to cool completely.
Tip: No spice grinder? Use the back of a small skillet to smash the seeds, then finely chop.