Place the softened butter, 1/4 cup of the sifted powdered sugar and the vanilla extract in a large mixing bowl, and cream together using an electric hand mixer. Add the rest of flour 1/2 cup at a time, continuing to mix until all the flour is incorporated. Add the chopped pecans, and mix well, about 1 minute. Cover the bowl with plastic wrap or a towel, and chill in the refrigerator for 1 hour.
Heat your oven to 400°. Remove the dough from the refrigerator, and shape the dough into 1” diameter balls. Shapes for this cookie can be a ball, a pointed oval, or a crescent. Continue to shape all of the cookies, and place on an ungreased cookie sheet.
Bake for 10-12 minutes until lightly golden, then remove from the oven, and immediately roll in the remaining powdered sugar while the cookies are still hot. Be careful, as the cookies are quite delicate. Cool the rolled cookies on a wire cookie rack. Once cooled, roll the cookies again in the powdered sugar. Store in an airtight container.