In a large bowl, combine the cooked rotini pasta, shredded chicken, cherry tomatoes, corn, bell pepper, red onion, and cheddar cheese.
In a separate small bowl, whisk together the BBQ sauce and ranch dressing until well combined.
Pour the dressing mixture over the pasta salad and gently toss until all ingredients are evenly coated.
Season with salt and pepper to taste, and toss again.
Cover the bowl with plastic wrap and refrigerate for at least 30 minutes to allow the flavors to meld.
Before serving, give the salad a gentle stir and garnish with fresh cilantro or parsley if desired.