1. Preheat broiler.
2. Cover baking sheet with foil; coat with cooking spray. Arrange tomato, bell peppers, onion, and zucchini on baking sheet; coat vegetables with cooking spray. Broil 16 minutes, stirring once. Remove vegetables from baking sheet; transfer to a large serving bowl.
3. Combine chipotle pepper and next 3 ingredients in a small bowl; stir with a whisk until blended. Pour over warm vegetables; toss gently to coat. Serve warm or chilled.
carbo rating: 7