Mash cake mix in large mixing bowl to get out all the lumps.
Add egg, vanilla, and melted butter.
Stir well to combine.
Refrigerate dough for 1 hour.
Meanwhile, unwrap Hershey’s Kisses. Set aside.
Remove refrigerated dough from refrigerator.
Place about ½ cup granulated sugar in small bowl.
Roll cookie dough into small balls.
Roll cookie dough into granulated sugar to coat well.
Place on cookie sheets that have been well sprayed with cooking spray.
Bake about 8-10 minutes at 350°.
Remove pans from oven and place a Hershey’s Kiss in center of cookie and press down.
Bake another 5-6 minutes or until done.
Let cool in pan about 5 minutes before removing to wire racks.