Divide the chicken, lettuce, tomatoes, onion, and cheese evenly among the tortillas.
2 cups cooked chicken, 2 cups chopped Romaine lettuce, 2 Roma tomatoes, 1/2 small red onion, 1/2 cup finely shredded colby jack cheese, 1/2 cup blue cheese crumbles, 4 8 to 10 inch flour tortillas