Line your air fryer basket, with with parchment paper.
Whisk together the flour, baking soda, salt, and cocoa. Set aside.
Beat the butter and medium speed for 5 minutes. Scrape down the sides. Add the sugar and continue beating for 5 to 7 minutes or until fluffy.
Add the egg, vanilla extract and food coloring, beating until evenly combined. Fold in the flour mixture and beat until mixed.
Slowly add the milk to the dough as the mixer runs, adding just enough to soften the dough.
Using a small (1 tablespoon) cookie scoop, portion the cookie dough and shape it into balls. Place on the parchment paper about 1 inch apart.
Set the tray into the air fryer and set the temperature to 320 degrees F, air fryer set, set the time for 8 to 10 minutes or until the cookies are puffed, and the edges are set. Cool the cookies on the baking sheet for 2 to 3 minutes before pressing one kiss into the center of each cookie.
Transfer to a wire rack and allow the cookies to cool completely. The candies will look like they are melting but do not disturb them, and they will resolidify in the correct shape.
Plate, serve, and enjoy!