Preheat oven to 375F.
Sift dry ingredients.
In large bowl, combine butter and peanut butter. Beat for 30 seconds at medium speed.
Add sugar and brown sugar; and beat until light in color and fluffy.
Add egg and vanilla; beat well.
Stir in flour mixture and beat until well blended.
Refrigerate, covered, 30 minutes to 1 hour.
Form dough into 1 inch balls.
Roll each ball into granulated sugar.
Place on parchment lined baking sheet.
Flatten with fork, dipped in flour, making a criss cross pattern.
Bake for 12-16 minutes to desired textured.
Cool 1 minute; remove to rack.
Enjoy!