Preheat oven. Preheat oven to 350°F. Line baking sheets with parchment paper.
Whisk together flour, cocoa powder, baking soda, baking powder, and salt. Set aside.
Beat softened butter, granulated sugar, and brown sugar until light and fluffy.
Beat in the eggs, milk, and vanilla extract.
Gradually add the dry ingredients and mix until the dough forms.
Scoop dough into tablespoon-sized portions and roll into balls.
Roll each dough ball generously in powdered sugar until completely coated.
Place cookies on prepared baking sheets and bake for 8–9 minutes.
Immediately press an unwrapped Hershey's Kiss upside down into the center of each warm cookie. Allow the cookies to rest on the baking sheet before transferring to a cooling rack.
Video
Notes
No chilling required! Use tablespoon-sized dough balls for approximately 30 cookies. Add ½ teaspoon of cornstarch to the powdered sugar before rolling for a more pronounced sugar coating after baking. Press the chocolate kisses into the cookies immediately after baking while they are still warm.