COOK noodles as directed on package.
MEANWHILE, heat dressing in large skillet on medium heat. Add chicken; cook and stir 5 to 7 min. or until done. Add tomatoes; cook 1 min., stirring occasionally.
DRAIN noodles, reserving 1/2 cup cooking water. Add noodles and reserved cooking water to chicken mixture in skillet; stir. Remove from heat. Add spinach, 1/2 cup cheese and the bacon; mix lightly. Sprinkle with remaining cheese.