Boil a large pot of salted water.
Add elbow macaroni and cook according to package instructions until al dente.
Drain the macaroni and rinse under cold water to cool.
In a large bowl, combine mayonnaise and Dijon mustard.
Add diced celery, bell peppers, red onion, and cherry tomatoes to the bowl.
Incorporate the cooled macaroni into the mixture.
Stir in chopped parsley and season with salt and pepper.
Taste and adjust seasoning as needed.
Chill in the refrigerator for at least 30 minutes before serving.
Serve cold and enjoy!