Bring a large pot of salted water to a boil, then cook the rotini until al dente, about 8–10 minutes per the package directions. Drain, rinse with cold water, and set aside to cool.

Brush the chicken breasts with olive oil, then season with smoked paprika, garlic powder, onion powder, kosher salt, and black pepper. Grill or cook in a skillet over medium-high heat for 6–7 minutes per side until nicely charred and the internal temperature reaches 165°F.

Brush the chicken with 1/4 cup barbecue sauce during the final minute of cooking, then rest for 5 minutes before dicing.

Whisk together the remaining 1/2 cup barbecue sauce, ranch dressing, and fresh lemon juice until smooth and creamy.

In a large bowl, combine the cooled rotini, diced BBQ chicken, cherry tomatoes, sweet corn kernels, red onion, shredded sharp cheddar cheese, cooked bacon, and green onions. Pour the dressing over the salad and toss gently until evenly coated.

Sprinkle with chopped fresh parsley and extra shredded sharp cheddar cheese if desired, then serve immediately or refrigerate for 1–2 hours before serving.