Cook elbow macaroni according to package directions. Drain but do not rinse. Set aside and let it cool.
In a bowl, combine all dressing ingredients. Whisk until well combined.
In a large bowl, combine macaroni, cheese, carrots, bell pepper, celery and onion. Pour the dressing to the salad. Toss gently until well combined.
Refrigerate for at least 4 hours but overnight is best; the salad will completely absorb the dressing. Note: Before serving, try the salad. Taste it and adjust accordingly. I added two more tablespoons of mayonnaise to my salad to make it creamier and it turned out great!