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

In a mixing bowl, cream together peanut butter, unsalted butter, brown sugar, and granulated sugar until smooth.

Add egg and vanilla extract, mixing until well combined.

Gently fold in flour, baking soda, and salt until a thick dough forms.

Scoop out 1-inch pieces of dough and roll into balls. Optionally roll in extra granulated sugar.

Place dough balls on prepared baking sheets, spaced about 2 inches apart.

Bake for 8-10 minutes, until puffed and edges appear set but centers are soft.

Press a chocolate kiss into the center of each cookie immediately after removing from the oven.

Let cookies cool on the baking sheets for 5 minutes before transferring to a wire rack.