Preheat the oven to 375°F. Line cookie sheets with parchment paper.

In a large mixing bowl or the bowl of a stand mixer fitted with the paddle attachment, combine the peanut butter, unsalted butter, sugars and salt. Cream together by beating on medium speed until well combined. Add the egg and vanilla. Beat until well combined. Scrape down the bowl. Add the flour and baking soda and beat on low speed just until combined.

Scoop the dough and roll into 1-inch balls. Coat in additional granulated sugar if desired. Place on a prepared baking sheet 2 inches apart.

Bake for 8 to 10 minutes or until the cookies look puffy and cracked and the bottom just start to turn brown. Immediately press a chocolate kiss into the center of each cookie. (The cookies will crack and that’s okay!) Allow the cookies to cool completely on the pan, until the chocolate is set. Serve or store in an airtight container for up to 1 week.