Preheat oven to 350°F. Prepare baking sheet by lining with parchment paper.
In a medium bowl, whisk together flour, cocoa powder and salt. Using an electric mixer and a large bowl (or a stand mixer), beat 1 cup of 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. Roll dough into approximately 1-inch balls and then toss in sugar to coat. Place one inch apart on parchment-paper lined baking sheets.
Bake for five minutes. Remove cookies from the oven and use the back of a small round measuring spoon (or a melon baller) to make an indentation in each cookie. Return to oven and bake for another 4 minutes. Cookies should be set but still look moist. Cool on the cookie sheets on wire racks.
While cookies cool, microwave chocolate chips and 1/4 cup of butter in a small bowl in 15 second increments. Stir well between each 15 seconds in the microwave, until completely melted. Stir in cherry extract. Let cool slightly so it thickens and you can pipe it without it running out and being a huge mess (about 5 minutes).
Spoon mixture into a zip-top bag or a disposable piping bag. Snip a small hole in one corner of the sip-top bag or the end of the piping bag. Pipe chocolate into indentations in cookies and finish with sprinkles (optional).