Quick Chicken with onion

1 tablespoon canola oil 2 1/2 lbs chicken breasts , 1 inch dice (5 breasts about 4 cups) 2 1/2 cups green bell peppers , diced 1 1/2 cups red bell peppers ,[...]

1 (16 ounce) package seasoned stuffing mix, bread cubes. I used Mrs. Culbertson brand. 3 to 4 cups 3 large celery ribs , thinly diced 3/4 cup diced onion 1[...]