Preheat oven to 375°F (190°C). Line a baking sheet with parchment paper.
In a medium bowl, whisk together flour, baking soda, and salt. Set aside.
In a large bowl, beat butter, granulated sugar, brown sugar, and peanut butter until creamy.
Add egg and vanilla extract; mix until combined.
Gradually stir in dry ingredients until dough forms.
Scoop dough into 1-inch balls, roll in sugar, and place 2 inches apart on the baking sheet.
Bake for 8–10 minutes, until edges are lightly golden.
Immediately press a chocolate kiss into the center of each cookie.
Cool on the baking sheet for 5 minutes before transferring to a wire rack.