Preheat the oven to 350˚F and line a rimmed baking sheet with parchment paper.

In a medium bowl, whisk together flour, baking powder, salt and anise seeds. Set aside.

In the bowl of a stand mixer fitted with the paddle attachment, combine butter and sugar. Mix at medium speed for 2 to 3 minutes, or until light and fluffy. Add the egg and vanilla extra and mix until incorporated.

Add the dry ingredients and process at low speed, just until a few streaks of flour remain. Remove the bowl from the stand mixer and fold any visible flour in by hand with a rubber spatula. Using a 1-tablespoon sized cookie scoop, scoop the batter, then roll into round balls. Place on the prepared pan, leaving about 2 inches between each cookie. Bake for 10 to 12 minutes, or until the cookies are slightly golden brown. Repeat with remaining cookie dough.

Transfer cookies to a cooling rack and let cool completely. While the cookies cool, make the glaze. In a medium bowl, whisk the powdered sugar with the milk until smooth and glossy.

Holding the cooled cookies upside down, dip the cookie tops in the glaze. Add desired sprinkles before the glaze sets. Allow cookies to sit for 10 to 15 minutes, or until the glaze hardens and sets.