Cook the rotini pasta according to package instructions until al dente, then drain and rinse under cold water.
In a large mixing bowl, combine the cooked pasta with cherry tomatoes, cucumber, bell peppers, broccoli, and red onion.
In a separate bowl, whisk together mayonnaise, yogurt, Dijon mustard, apple cider vinegar, salt, and pepper until smooth and well combined.
Pour the dressing over the pasta and vegetables, then gently toss until evenly coated.
Taste and adjust seasoning, adding more salt or pepper if needed.
Cover the bowl with plastic wrap or a lid and refrigerate for at least 30 minutes before serving.
Toss the salad gently one more time before serving to redistribute the dressing.