Whisk baking soda, flour, and salt. Set that bowl aside for now.
In another large bowl, beat the unsalted butter at high speed till creamy, either with a stand or handheld mixer. Then, dial down to medium-high and add granulated sugar (¼ cup) and brown sugar. Beat again until it's smooth and creamy (around 2 minutes).
Cack in the large egg and cream until combined (1 minute). Scrape the bowl's bottom and sides as you go. Add the creamy peanut butter and a dash of vanilla extract, beating until nicely mixed.
Slowly add your flour mixture (from Step 1) to those wet ingredients. Beat at low speed until well combined. Our peanut butter cookie dough will be pretty creamy and soft at this point. Cover and refrigerate it for an hour or longer.
Preheat your oven to 350°F. Line two baking sheets with parchment paper or silicone mats.
Scoop about a tablespoon of dough for each cookie and ball it up. Then, roll each dough ball in sugar (about ½ cup). Pop them onto the parchment-lined baking sheets 2 ¾ to 3 inches apart so they have plenty of room to spread out.
Bake them for 10 to 15 minutes until their tops crack slightly. Let them cool on their baking sheets (out of the oven) for about 5 minutes.
Bring out the chocolate kiss candies! Press each into the cookie's center. Grab a spatula and gently transfer your cookies to one big plate (or some smaller ones). Be careful since they're still soft.
Pop them in the freezer (about 10 minutes) to set your chocolate.
Take them out of your freezer and dig in.