📖 Instructions

1. Before anything else, take out your unsalted butter and large egg from the fridge. They need to come to room temperature, which usually takes about 30-60 minutes. This is super important because room temperature ingredients blend together much more smoothly, giving you a consistent dough texture. While they're chilling, line a large baking sheet with parchment paper. If you don't have parchment, you can lightly grease the sheet, but parchment makes cleanup a breeze and prevents sticking.
2. Preheat your oven to 375°F (190°C). Getting the oven to the correct temperature before the cookies go in is key for an even bake. Also, in a medium bowl, whisk together the all-purpose flour, baking soda, and salt. Make sure to really combine them well. This ensures that the leavening agent (baking soda) and salt are evenly distributed throughout the dough, preventing any weird salty or flat spots in your cookies. Set this dry mixture aside for a moment.
3. In a large bowl, using an electric mixer (either a stand mixer with the paddle attachment or a hand mixer), beat together the softened unsalted butter, granulated sugar, and packed light brown sugar on medium speed. You'll want to beat this for about 2-3 minutes until the mixture looks light and fluffy. This process is called creaming, and it incorporates air into the butter and sugar, which contributes to the cookies' soft and chewy texture.
4. Now, add the creamy peanut butter to the butter and sugar mixture. Continue beating on medium speed for another 1-2 minutes until everything is well combined and smooth. Be sure to scrape down the sides of the bowl with a rubber spatula to ensure all the peanut butter is incorporated. This step guarantees a rich, even peanut butter flavor in every bite.
5. Next, crack in the room temperature large egg and add the vanilla extract. Beat on medium speed until these are fully incorporated, about 1 minute. The mixture might look a little curdled at first, but keep beating until it comes together and is smooth again. The egg acts as a binder, and the vanilla adds a lovely depth of flavor.
6. Gradually add the dry ingredients (flour, baking soda, salt mixture) to the wet ingredients. Mix on low speed until just combined. It's crucial not to overmix the dough at this stage. Overmixing can develop the gluten in the flour too much, resulting in tough, dry cookies. Stop mixing as soon as you see no more streaks of flour.
7. Time to make those famous crisscross patterns! Scoop out tablespoon-sized portions of dough and roll them into smooth balls between your palms. Place the dough balls about 2 inches apart on your prepared baking sheet. Using a fork, gently press down on each cookie ball to flatten it slightly. Then, rotate the fork 90 degrees and press down again to create the classic crisscross pattern. Don't press too hard, just enough to flatten and make the design.
8. Bake the cookies in your preheated oven for 10-12 minutes. You'll know they're done when the edges are lightly golden brown, but the centers still look a little soft and underbaked. This is the secret to a chewy cookie! Remember, oven temperatures can vary, so keep an eye on them. If your oven has hot spots, you might need to rotate the baking sheet halfway through baking.
9. Once baked, remove the baking sheet from the oven and let the cookies cool on the sheet for 5-7 minutes. This allows them to set up and prevents them from falling apart when you move them. If you try to move them too soon, they'll be too delicate. After this initial cooling, transfer the cookies to a wire rack to cool completely. Cooling on a rack allows air to circulate around them, preventing sogginess.