Cook the pasta: Bring a large pot of generously salted water to a boil. Add the rotini and cook according to package directions until just al dente (pull it 30 seconds early — it firms up beautifully in the dressing). Drain in a colander, rinse under cold running water until the pasta is completely cool to the touch, and let it drain thoroughly.

Whisk the dressing: In a large mixing bowl, whisk together the mayonnaise, BBQ sauce, apple cider vinegar, garlic powder, chili powder, ½ teaspoon salt, and ¼ teaspoon black pepper until smooth and uniform in color.

Combine: Add the cooled rotini, diced red bell pepper, sliced English cucumber, diced red onion, chives, and parsley (or cilantro) to the bowl with the dressing. Fold gently with a rubber spatula until every piece is evenly coated — avoid aggressive stirring, which bruises the vegetables.

Chill and serve: Taste and adjust salt, pepper, or vinegar to your preference. Cover and refrigerate for at least 30 minutes before serving to let the flavors meld. Give it one more stir and a final taste right before serving — chilling mutes seasoning slightly, so a small pinch more salt may be needed.