Homemade 'Hershey's Syrup'

"[Photograph: Rosco Weber] To be perfectly honest, I enjoy this syrup best with only 5 ounces of brown sugar. The lower sugar version makes a deep, rich, sophisticated chocolate syrup. But not "Hershey's Syrup." The absolute hallmark of Hershey's is its sweetness, so to stay true to your childhood memories, stick with 9 ounces. For the chocolate, I recommend something with a minimum cocoa content of 50% but no higher than 60%. Higher percentages give the syrup too dark a flavor while milk chocolates lack the depth of flavor. I use Callebaut 54% at work and have tested Chocolove 55% and Dagoba 59% at home (as those brands are widely available in gourmet-type groceries) with great success. Note: All measurements are in weights, as volume measures can be very imprecise. I strongly recommend using a scale for all pastry projects. Serious Eats' recommended kitchen scale is the Oxo Good Grips Scale with Pull Out Display...."