Dense with double the peanut butter, these cookies are ultra-soft at the center with delicately crumbly edges and a light sugar crust for pure peanut butter bliss.
Whisk the flour, baking powder, baking soda, and salt together in a medium bowl; set aside.
Using a hand mixer or stand mixer fitted with a paddle, cream the butter, granulated sugar, and brown sugar on medium speed until smooth, about 1–2 minutes.
Add the eggs and beat on high until combined, about 1 minute; scrape down the bowl as needed.
Add the peanut butter and vanilla; beat on high until combined.
Add the dry ingredients to the wet ingredients and mix on low until combined; with the mixer running on low, add the chopped peanuts if using. Dough will be thick and soft.
Cover and chill the dough in the refrigerator for 1 hour (up to 2–3 days). If chilling longer than a few hours, let sit at room temperature for at least 30 minutes before rolling and baking.
Preheat the oven to 350°F (177°C). Line 2–3 large baking sheets with parchment paper or silicone baking mats.
Roll dough into balls, about 1.5 tablespoons each, then roll in granulated sugar. Use a fork to make a crisscross pattern on top of each ball.
Bake for 10–12 minutes, until very lightly browned on the sides; centers will look very soft.
Cool on the baking sheets for 5 minutes, then transfer to a wire rack to cool completely.
Storage: Cookies stay fresh covered at room temperature for up to 1 week.