Preheat oven to 350°F (175°C) and line two baking sheets with parchment paper.
In a large bowl, cream together the softened butter, granulated sugar, and brown sugar for 2–3 minutes until light and fluffy.
Beat in the creamy peanut butter until fully combined, then add the egg and vanilla extract and mix until smooth.
In a separate bowl, whisk together the all-purpose flour, baking soda, and salt.
Gradually add the dry ingredients to the wet mixture, mixing on low speed until just combined.
Scoop tablespoon-sized portions of dough and roll into balls. Place on prepared baking sheets 2 inches apart.
Flatten each dough ball with a fork in a crisscross pattern, dipping the fork in sugar to prevent sticking.
Bake for 10–12 minutes until edges are lightly golden but centers still look slightly underdone.
Cool on the baking sheet for 5 minutes, then transfer to a wire rack to cool completely.
