1. Preheat and Prepare: Preheat your oven to 350°F (175°C). Line two large baking sheets with parchment paper or silicone baking mats. Set aside.
2. Cream Butter and Sugars: In a large mixing bowl, use an electric mixer to cream together the softened butter, granulated sugar, and brown sugar on medium speed for about 2-3 minutes until light and fluffy. The mixture should look pale and airy. Scrape down the sides of the bowl as needed.
3. Add Wet Ingredients: Beat in the peanut butter until fully combined and smooth, about 1 minute. Add the egg and vanilla extract, mixing until just incorporated. The mixture should look smooth and creamy.
4. Combine Dry Ingredients: In a separate medium bowl, whisk together the flour, baking soda, and salt until evenly distributed.
5. Mix the Dough: Add the dry ingredients to the wet ingredients in two additions, mixing on low speed just until combined after each addition. Do not overmix—stop as soon as you no longer see flour streaks. The dough will be thick and slightly sticky.
6. Shape the Cookies: Place some granulated sugar in a small bowl. Using a 1.5-tablespoon cookie scoop or your hands, roll the dough into balls about 1.5 inches in diameter. Roll each ball in the granulated sugar to coat completely, then place on the prepared baking sheets about 2 inches apart.
7. Create Crisscross Pattern: Using a fork, gently press down on each cookie ball to flatten it slightly, creating a crisscross pattern. Press once vertically, then once horizontally. The cookies should be about ½ inch thick after pressing.
8. Bake: Bake for 9-11 minutes, or until the edges are just set and lightly golden. The centers will look slightly underdone—that’s perfect! They’ll continue cooking on the hot baking sheet after you remove them from the oven.
9. Cool: Let the cookies cool on the baking sheet for 5 minutes (this is crucial for the right texture), then carefully transfer them to a wire cooling rack to cool completely. They’ll firm up as they cool.
10. Serve and Enjoy: Serve warm or at room temperature. Store leftovers in an airtight container at room temperature for up to 5 days, or freeze for up to 3 months.

For 3-Ingredient Version: Simply mix the peanut butter, sugar, and egg together until smooth. Roll into balls, press with a fork, and bake at 350°F for 8-10 minutes. That’s it!