Break the chocolate into pieces (or roughly chop it) and place it in a microwave-safe bowl. Heat in 20-second intervals, stirring each time until melted and smooth. Set aside to cool.
In the bowl of a food processor, add the butter, powdered sugar, cocoa powder, and salt. Process at high speed for 30-60 seconds until smooth, scraping down the sides of the bowl as needed.
Add the corn syrup and vanilla extract, and process again until just combined, about 10 seconds.
Scrape down the sides of the bowl, then pour in the melted chocolate. Pulse the mixture in short bursts (about 10 to 15 one-second pulses) until the frosting is creamy and smooth.
Once the cake has fully cooled, spread the frosting evenly over the top.
Enjoy your rich and indulgent chocolate cherry cake!