Preheat oven to 350°F. Prepare baking sheets by lining with parchment paper or silicone sheets.
In a medium bowl, whisk together flour, cocoa powder and salt.
Using an electric mixer and a large bowl (or a stand mixer), beat butter and 1 cup of sugar on medium-high until light and fluffy (about 3 minutes). Add egg and vanilla and beat until combined. Turn mixer to low and gradually add flour mixture until combined.
Put the remaining 1/2 cup of sugar in a small bowl. Form dough into approximately 1-inch balls and then roll in sugar to coat. Place one inch apart on prepared baking sheets.
Bake for 8 minutes or until cookies are set but still look moist. Remove from the oven and lightly press in candy cane kisses into the center of each cookie.
Cool completely on the cookie sheets on wire racks before removing to an airtight container to store.
Make sure that you have the kisses unwrapped and ready to go so you can put them on top of the cookies immediately after they come out of the oven.
Yield depends on size of cookies.
If desired, substitute a different type of Hershey's Kisses.
Each 10 oz. bag of candy kisses contains 70-75 kisses (so you'll have extra to eat!).