Preheat your oven to 350°F (180°C) and line a baking sheet with parchment paper.
Cream together the butter, peanut butter, granulated sugar, and brown sugar until light and fluffy using either a stand mixer with a paddle attachment or a handheld mixer.
Add the egg and vanilla extract and mix until well combined.
In a separate bowl, whisk together the flour, baking powder, baking soda, and salt.
Sift the dry ingredients into the wet ingredients and mix until just combined.
Using a cookie scoop (or a spoon), form cookie dough balls and place them onto the prepared baking sheet with enough space in between each cookie to allow for spreading.
Bake for 10-12 minutes or until the edges are golden brown and the centers are just set. Do not overbake, as the cookies will continue to cook as they cool.
Allow the cookies to cool on the baking sheet for 5 minutes before transferring them to a wire rack to cool completely.
Enjoy your freshly baked peanut butter cookies!