Preheat your oven to 350°F (175°C). Line two baking sheets with parchment paper.

In a large bowl, beat together peanut butter, butter, granulated sugar, and brown sugar until light and fluffy.

Mix in the egg and vanilla extract, scraping down the sides until fully combined.

In a separate bowl, whisk flour, baking soda, and salt. Gradually add to the peanut butter mixture and stir until a soft dough forms.

Shape dough into 1-inch balls and roll each ball in extra granulated sugar to coat.

Place on prepared baking sheets about 2 inches apart. Bake 8–10 minutes until edges are set but centers are still soft.

Immediately press one chocolate kiss into the center of each warm cookie. Allow cookies to cool on the baking sheet for 5 minutes, then transfer to a wire rack.