Preheat the oven to 350°F (175°C). Line two baking sheets with parchment paper.
In a medium bowl, mix together the peanut butter, granulated sugar, egg, and baking soda until well combined.
Roll the dough into 1-inch balls and place them 2 inches apart on the prepared baking sheets.
Use a fork to gently flatten each ball and create a crisscross pattern on top.
Bake the cookies for 8 to 10 minutes until they are set but still soft in the center.
Remove the cookies from the oven and immediately press one Hershey’s Kiss into the center of each cookie.
Allow the cookies to cool on the baking sheet for 5 minutes before transferring them to a wire rack to cool completely.