Preheat oven to 375°F (190°C) degrees. Line a cookie sheet with parchment paper.
In a medium mixing bowl, whisk together the flour, baking soda, and salt. Set aside.
In a large bowl, (I use my stand mixer with my paddle attachment, but a hand mixer also works) cream together the sugars and butter on medium speed until light and fluffy about 2-3 minutes. Scrap down the bowl as needed.
Add in the egg to the butter mixture and beat to combine. Mix in peanut butter and vanilla until smooth and creamy.
Stir in the dry ingredients until just combined. Do not overmix.
Using a small cookie scoop, scoop about 2 tablespoons of dough and roll into balls with your hands and then roll in sugar. Place on baking sheet and flatten with fork. I flatten with a criss cross.
Bake for 10-12 minutes until edges are set and middles are still slightly soft. Remove from the oven and allow to cool on the baking sheet for 5 minutes. Transfer to a wire rack to continue cooling.