Cream butter and sugar in medium bowl until creamy. Add vanilla,; beat until well mixed.
Add flour and pecans; beat at low speed, scraping bowl occasionally, until well mixed.
Shape dough into 1 inch balls. Place 1 inch apart onto ungreased cookie sheets. Bake 16-19 minutes or until very lightly browned. Cool 5 minutes; roll in powdered sugar while still warm and again when cool.
Notes
Tip #1 - Pecans can be purchased as halves or pieces. Finely chop by hand or pulse a few times in a food processor to save time.Tip #2 - These cookies have many names depending on where you live! Russian Tea Cakes, Mexican Wedding Cake and snowball are all similar cookies with just slight variations.