Cook macaroni to al dente according to package directions, drain and rinse. Transfer to large bowl, let cool.
While macaroni cooks and cools, chop red onion, bell peppers, parsley and dice carrot, set aside.
Add red onion, bell peppers, parsley, carrot, mayonnaise, mustard and salt and pepper to macaroni.
Mix well, refrigerate until cool. Serve cold or at room temperature.
Notes
Swap some mayo with Greek yogurt. Creamy vibes, fewer points—win-win!Chop veggies small. Makes every bite colorful, crunchy, and kid-approved.Let it chill, like really chill. An hour in the fridge = flavor magic.