Add chicken and pasta, then carrots, bell pepper, mushrooms, onions, garlic, soy sauce, cornstarch, sugar, broth and oil to large stockpot. Cover, bring to a rolling boil over high heat and stir. Reduce heat to medium-low and cook, covered, 15 minutes, stirring occasionally, or until most of the liquid is gone and the chicken is cooked through.

Remove from heat, uncover and let sit 5 minutes before serving.