Heat oil in large saucepan over medium-high heat until hot. Add onions and bell pepper; cook and stir 1 to 2 minutes or until crisp-tender. Add chicken; cook and stir 2 minutes.
Add all remaining ingredients; mix well. Bring to a boil. Reduce heat to medium-low; simmer 10 minutes or until chowder is thoroughly heated and chicken is no longer pink, stirring occasionally.