Preheat your oven to 375°F (190°C). Line two large baking sheets with parchment paper or silicone baking mats. Unwrap all of the chocolate kisses and set them aside.

In a large mixing bowl, use an electric mixer to cream together the softened butter, 1/2 cup granulated sugar, and light brown sugar until the mixture is light and fluffy, about 2 to 3 minutes.

Beat in the peanut butter until fully combined. Add the egg and vanilla extract and mix until just blended, scraping down the sides of the bowl as needed.

In a separate medium bowl, whisk together the all-purpose flour, baking soda, and salt. Gradually add the dry ingredient mixture to the wet mixture, mixing on low speed until the dough comes together and no streaks of flour remain. Do not overmix.

Pour the reserved 1/4 cup of granulated sugar into a small, shallow dish for rolling the cookie dough. Scoop the dough using a small cookie scoop (about 1 tablespoon) or roll the dough into uniform balls, approximately 1 inch in diameter.

Roll each dough ball thoroughly in the dish of granulated sugar to coat all sides completely. Place the sugared dough balls onto the prepared baking sheets, spacing them about 2 inches apart.

Bake the cookies for 8 to 10 minutes. The cookies should be lightly golden brown and appear set, but they should still look slightly soft in the center.

Immediately upon removing the cookies from the oven, gently press one unwrapped chocolate kiss firmly into the center of each hot cookie. The pressure should cause the cookie to crack slightly around the edges.

Cool the cookies on the baking sheet for 5 minutes before carefully transferring them to a wire rack to cool completely. Do not move or touch the chocolate kisses until the chocolate has fully set (about 1 hour).