Heat oven to 350°F; parchment-line two sheets. Beat butter and sugar 2 minutes; add eggs, anise, and vanilla.

Whisk flour, baking powder, and salt; mix into butter with dough milk just until soft dough forms.

Divide into 30 portions. Roll into 4-inch ropes; tie loose knots and space 2 inches apart.

Bake one sheet at a time 11 to 12 minutes until bottoms lightly golden and tops set. Rack-cool completely.

Whisk powdered sugar and glaze milk smooth. Dip tops; add measured sprinkles. Dry at least 45 minutes before stacking.