Preheat oven to 375°F. In a medium-size mixing bowl, whisk together flour, baking soda, and salt until combined. Set aside.

Combine butter, peanut butter, 1/2 cup granulated sugar, and brown sugar in the bowl of a heavy-duty stand mixer. Beat on medium-high until light and fluffy, 3 minutes.

Scrape down sides of bowl and add eggs one at a time, beating until fully incorporated before adding the second. Add vanilla and milk, and beat on medium-high until airy and doubled in volume, about 2 minutes.

Add flour mixture to wet ingredients and incorporate on low speed until just combined, about 1 minute.

Place remaining 1/4 cup granulated sugar in a small bowl. Portion dough into 1 1/2-inch balls and roll in granulated sugar. Place sugar coated dough balls 2 inches apart on a parchment paper-lined baking sheet.

Bake for 7 minutes, remove from oven, press 1 of the Hershey’s kisses into the center of each puffed dough ball (the dough will crack and create a rounded crater around the Hershey’s kisses). Return to the oven and bake until light golden brown, 3-5 minutes. Transfer to wire racks to cool completely, about 15 minutes.