A deliciously decadent chocolate cookie, coated in sugar, and topped with a chocolate kiss, Hershey's Kiss Cookies are a perfect holiday treat that everyone will love! Want my advice? Make a lot of these, because they will disappear quite quickly!
Preheat oven to 350°F. Prepare a baking sheet by lining it with parchment paper or a silicone baking mat. Set aside.
In a large mixing bowl, beat together the butter and both sugars until creamy and smooth. About 2-3 minutes.
Add the egg yolk and vanilla extract. Beat to incorporate.
Sift together the flour, cocoa powder, baking soda, and salt. Add to the butter mixture and beat on low speed until just mixed in.
Roll mixture into balls using 1 1/2 teaspoons of the dough for each cookie. Roll in the sanding sugar and place on the prepared baking sheet. Leave two inches of space between each cookie.
Bake for 10 minutes. Remove from oven and place a Hershey's Kiss in the center of each cookie. Push the chocolate down into the baked cookie until you feel slight resistance.
Allow the cookies to cool on the baking sheet for 3 minutes. Carefully transfer to a wire cooling rack to finish cooling or until the chocolate has hardened.