In a medium mixing bowl, whisk together the all-purpose flour, baking soda, and salt until well combined. Set aside.

In the bowl of a stand mixer fitted with the paddle attachment (or using a hand mixer), cream together the creamy peanut butter, unsalted butter, granulated sugar, and light brown sugar on medium-high speed for about 2–3 minutes, or until the mixture is light and fluffy.

Add the egg, milk, and vanilla extract, and mix until fully incorporated, scraping down the sides of the bowl as needed.

Reduce the mixer speed to low and gradually add the dry ingredients, mixing just until a soft, uniform dough forms—do not overmix.

Cover the bowl tightly with plastic wrap (or transfer the dough to an airtight container), and chill the dough for at least 1 hour to firm up. This step helps prevent excess spreading during baking.

Once chilled, preheat your oven to 375°F (190°C) and adjust the oven rack to the second level (just above center). Line two baking sheets with parchment paper or silicone baking mats.

Using a spoon or cookie scoop, form the dough into 1-inch balls. Roll each ball in granulated sugar to coat evenly, then place on the prepared baking sheets, spacing them 1½ to 2 inches apart.

Bake the cookies for 7–8 minutes, then remove them from the oven and immediately press a Hershey’s Kiss into the center of each cookie. The edges will crack slightly—that’s the signature look of a peanut butter blossom.

Return the cookies to the oven and bake for an additional 2 minutes to slightly melt the chocolate and help set it into the cookie.

Remove the baking sheets from the oven and let the cookies cool for 5–10 minutes before transferring them to a wire rack to cool completely.

Storage tip: Store cooled cookies in an airtight container with a slice of bread to help keep them soft. Cookies will stay fresh for up to 1 week at room temperature.