Preheat oven to 350 degrees F.
Optional: Spread pecans on a cookie sheet. Once the oven is preheated, bake the pecans for 3-5 minutes, until they smell nutty and maple-like. Watch closely and do not overbake; they will burn easily!
Place cooled pecans in a food processor and grind them into a powder. Combine pecan powder with flour.
In a separate bowl, cream together butter and sugar. Mix in vanilla before adding the flour pecan mixture. Mix until completely combined.
Place tablespoons of batter on a greased cookie sheet and bake for 30 minutes at 300 degrees F.
While cookies are hot, dust with powdered sugar. If a glaze is preferred, return sugared cookies to pan and place in hot oven for 1 minutes. Transfer to a wire rack to cool.