In a small bowl, whisk together the first four ingredients. Place 3 Tbsp. in a large resealable plastic bag. Add vegetables, seal and toss to coat. Let marinate for 1-1½ hours at room temperature. Reserve remaining marinade.
Preheat grill to medium heat. Transfer vegetables to a grilling basket or pan coated with nonstick cooking spray; cover with foil. (Or, wrap vegetables in foil coated with nonstick spray.) Grill for 8-12 minutes until crisp-tender, turning occasionally. Place vegetables on a large serving plate. Drizzle with reserved marinade. Makes 6-8 servings.