With an electric mixer, cream butter and sugar until smooth. Add eggs, one at a time, beating after each addition. Add the anise and vanilla, blending thogoughly. When the batter is light and fluffly, add baking powder and anise seed and mix well. Add flour, one cup at a time, blending after each addition. Wrap in wax paper and refrigerate 6 to 8 hours. Shape into walnut-size balls, and place 2 inches apart on a greased cookie sheet. Bake in a preheated oven at 400° for 15 minutes or until cookies are golden.