Preheat Oven: Preheat oven to 375°F (190°C). Line baking sheets with parchment paper.
Mix Dry Ingredients: In a medium bowl, whisk together flour, baking soda, and salt. Set aside.
Cream Butter and Sugars: In a large bowl, beat softened butter, peanut butter, granulated sugar, and brown sugar until creamy and smooth.
Add Egg and Vanilla: Beat in egg and vanilla extract until fully incorporated.
Combine Wet and Dry Ingredients: Gradually add the flour mixture to the wet ingredients, mixing until just combined.
Form Cookie Balls: Scoop 1 tbsp of dough and roll into balls. Roll each ball in granulated sugar to coat.
Bake the Cookies: Place dough balls 2 inches apart on prepared baking sheets. Bake for 10–12 minutes, until edges are lightly golden but centers are soft.
Add Hershey’s Kisses: Immediately press one Hershey’s 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 to cool completely.