In a 2-quart saucepan, combine grapes, grapefruit juice, honey, ginger, grapefruit zest and thyme. Bring to boil over medium heat, then reduce heat to medium-low.
Cook until grapes begin to blister and burst, about 5 minutes.
Mash grapes with the back of a spoon or potato masher to create a chunky texture. Cook for an additional 5 minutes.
In a small bowl, whisk together cornstarch and 1 tablespoon water to create a slurry.
Pour slurry into the saucepan with grape mixture and mix well. Cook 1 minute or until the mixture thickens. Remove from heat.
Serve sauce warm or cold; if serving cold, transfer sauce to a shallow, covered container and refrigerate.
Marcy Gaston, MS, RD, LN, is Assistant Teaching Professor of Hospitality Management at Montana State University in Bozeman. She blogs at cookingsustainably.com. Follow her on Twitter and Instagram.
