heat oven to 350 F and line 2 baking sheets with parchment paper
whisk flour baking soda and salt until evenly combined.
Make Dough
beat butter granulated sugar and brown sugar until light and creamy
beat in peanut butter then egg and vanilla until smooth
mix in dry ingredients just until no dry streaks remain
if dough feels very soft chill 20 to 30 minutes for easier shaping.
Shape And Bake
scoop 1 tbsp portions and roll into balls then roll in optional sugar
place 2 inches apart and flatten with a fork in a crisscross pattern
bake until edges are set and lightly golden and centers look slightly underdone 9 to 11 minutes
cool on the sheet 5 minutes then transfer to a rack to cool completely.
Notes
1. For extra chew add 1 tbsp milk to the dough; Swap crunchy peanut butter for texture; Do not overbake for soft centers; Measure flour by spooning into the cup and leveling; Store airtight up to 5 days or freeze baked cookies up to 2 months