Cook the rotini pasta according to package instructions. Drain and rinse under cold water to cool.
In a large bowl, combine the cooked pasta, shredded chicken, cherry tomatoes, corn, red onion, and cheddar cheese.
In a separate small bowl, whisk together the ranch dressing, BBQ sauce, olive oil, garlic powder, salt, and pepper until well combined.
Pour the dressing mixture over the pasta salad and toss gently until everything is evenly coated.
Cover the bowl and refrigerate for at least 30 minutes to allow the flavors to meld.
Before serving, give the salad a gentle toss and garnish with fresh cilantro or parsley if desired.