Cream the Wet Ingredients: In a stand mixer, combine brown sugar, white sugar, peanut butter, and softened butter. Mix until smooth and creamy (2-3 minutes). Incorporate the egg and vanilla extract, mixing until fluffy.

Combine the Dry Ingredients: In a separate bowl, whisk together flour, baking soda, and salt. Ensure even distribution of the baking soda.

Combine Mixtures: Gradually add dry ingredients to the wet mixture in the stand mixer. Mix on low speed until just combined.

Chill the Dough: Transfer dough to a bowl, cover with plastic wrap, and refrigerate for 1 hour.

Preheat the Oven: Preheat your oven to 375°F (190°C).

Prepare the Baking Sheet: Line a baking sheet with parchment paper.

Shape the Cookies: Scoop 1.5 tablespoons of dough, roll into balls, place on the baking sheet 2 inches apart, and flatten slightly with a fork.

Bake: Bake for 9-11 minutes or until edges are lightly golden; centers should be soft.

Cool: Let the cookies sit for 5 minutes before transferring to a wire rack to cool completely.