Bring a large pot of water to a boil. Add a pinch of salt, then toss in the rotini pasta. Cook according to the package instructions until al dente. Once cooked, drain the pasta and rinse it under cold water to stop the cooking process. Set aside to cool.

If using raw chicken, season it with salt and pepper. Grill or pan-sear the chicken until it reaches an internal temperature of 165°F (about 7-10 minutes on each side). Let it rest for a few minutes before dicing into bite-sized pieces.

While the chicken is cooling or cooking, dice the fresh pineapple, red bell pepper, celery, and green onions into small pieces. Grate the carrots if using fresh.

In a medium bowl, combine the mayonnaise, Greek yogurt (or sour cream), honey, soy sauce, garlic powder, black pepper, and salt. Whisk together until smooth.

In a large mixing bowl, add the cooled pasta, diced chicken, chopped vegetables, and pineapple. Pour the dressing over the top and gently toss everything together until well-coated.

Cover the bowl with plastic wrap and refrigerate the salad for at least 30 minutes to allow flavors to meld. Before serving, give it a gentle stir and garnish with fresh cilantro if desired.