Make the chocolate glaze: In a 1-quart saucepan bring the sugar, water, and chocolate to to a boil over medium-high heat, stirring occasionally. Attach a candy thermometer to the pan. Reduce the heat to medium and cook, uncovered, stirring occasionally, until the mixture reaches 234ºF (112ºC)., about 5 minutes. Remove from the heat. Pour into a glass measuring cup (do not scrape out the saucepan). Let stand, stirring often, until slightly cooled and lightly thickened, 2 to 3 minutes.