Place grapes in food processor bowl; process with 3 or 4 on-off turns until coarsely chopped; set aside. In a large skillet melt butter; add onion and cook until just tender. Add rosemary and oregano. Cook for 1 minute. Add chopped grapes and vinegar; cook 1 to 2 minutes more or until heated through. Transfer to serving bowl. Serve using a slotted spoon. Makes 24 (2 tablespoon) servings.