Preheat oven to 375°F (190°C) and line baking sheets with parchment paper.

In a medium bowl, whisk together flour, baking soda, and salt; set aside.

In a large bowl, cream together softened butter, granulated sugar, and brown sugar until light and fluffy.

Beat in the peanut butter until well combined, then add the egg and vanilla extract, mixing until just incorporated.

Gradually add the dry ingredients to the wet ingredients, mixing until a soft dough forms.

Roll the dough into 1-inch balls, then roll each ball in the remaining granulated sugar.

Place the sugared dough balls about 2 inches apart on the prepared baking sheets.

Bake for 8-10 minutes, or until the edges are lightly golden and the centers are still soft.

Immediately after removing from the oven, press one chocolate kiss into the center of each hot cookie.

Let the cookies cool on the baking sheets for a few minutes before transferring them to a wire rack to cool completely.