Preheat the oven to 350 degrees. Line 2 baking sheets with parchment paper; set aside.

In a medium bowl, whisk together the flour, cocoa, and salt; set aside.

In a large bowl, using a handheld mixer beat the butter on medium-high speed until smooth about 1 minute. Add the sugar and beat on medium-high speed until creamed, about 2 minutes. Add the egg yolk, milk, and vanilla extract, beat on high speed until combined, about 1 minute.

Add the dry ingredients to the wet ingredients and mix on low speed until combined.

Pour the sprinkles into a small bowl; set aside.

Roll tablespoon-size balls of cookie dough in sprinkles and place on the prepared baking sheets 2-inches apart.

Bake the cookies for 10-12 minutes. Remove the cookies from the oven and allow them to cool on the baking sheet for 5 minutes. Press the chocolate kisses into the center of each cookie.

Transfer the cookies to a wire rack to cool completely. Cookies will keep in an airtight container at room temperature for up to 1 week.