COOK and stir onions in hot oil in large skillet until crisp-tender.
ADD tomatoes, carrots and broth; mix well. Bring to boil on medium-high heat; simmer on medium-low 15 min. or until vegetables are tender, stirring occasionally.
BLEND vegetable mixture, in small batches; in blender until smooth, blending dressing and chipotle peppers with the last batch. Serve warm or chilled.