Preheat oven to 350 degrees.
In a stand mixer, combine butter, peanut butter, sugar, and brown sugar.
Add egg and vanilla, continuing to mix.
Slowing incorporate dry ingredients into stand mixer, continuing to mix.
Shape into 1 ½ inch balls and arrange on a lined baking sheet.
Slightly flatten each ball of dough with a fork to make the cross hatch pattern on top.
Bake 8-9 minutes.
sprinkle with sugar once directly out of oven if desired for top coating
