Heat oven to 325°F. In small bowl, mix flour, baking powder, baking soda and salt; set aside.
2 In large bowl, beat granulated sugar, softened butter and seeds from 2 vanilla beans with electric mixer on medium speed about 1 minute or until fluffy; scrape side of bowl. Beat in eggs, one at a time, just until smooth. On low speed, beat flour mixture into sugar mixture until well blended. Cover and let dough stand at room temperature 10 minutes.
3 Shape dough into 60 (1 1/4-inch) balls. In small bowl, place 1 cup powdered sugar. Roll each cookie in powdered sugar; shake off excess. Place on ungreased cookie sheets 2 inches apart.
4 Bake 12 to 14 minutes or until edges are until light brown. Cool 2 minutes; remove from cookie sheet to cooling rack. Cool completely, at least 15 minutes. Sprinkle with additional powdered sugar. Store in airtight container at room temperature.