1. Combine dressing, soy sauce, and pepper flakes in a medium bowl; add chicken, tossing to coat.
2. Heat oil in a large nonstick skillet over medium-high heat. Add snow peas and bell pepper; stir-fry 2 minutes. Add chicken mixture; stir-fry 3 minutes. Add onions; stir-fry 1 minute or until chicken is thoroughly heated and vegetables are crisp-tender. Top with cilantro.