Whisk together sugar and cornstarch in a medium skillet; whisk in orange juice. Cook over medium heat, whisking constantly, 2 minutes or until thickened. Stir in cherries, and, if desired, orange zest. Bring to a boil over medium heat; reduce heat, and simmer, stirring often, 5 minutes.
Remove from heat.
Stir in brandy, and return to heat. Cook, stirring constantly, 30 seconds. Cool slightly.