Take the meat off the rotisserie chicken. Remove the skin and bones. Shred the chicken into bite-sized pieces using two forks. Place everything into a large mixing bowl.

Wash the celery, parsley, and onion well. Chop them into very small pieces. Smaller pieces spread evenly through the salad and create a better texture in every bite.

In a small bowl, combine mayonnaise, Greek yogurt, Dijon mustard, lemon juice, garlic powder, onion powder, salt, and black pepper. Stir well until the dressing becomes smooth and creamy.

Pour the dressing over the shredded chicken. Add chopped celery, onion, parsley, grapes, and nuts if using. Mix gently until every ingredient is coated with the creamy dressing.

Taste the chicken salad before chilling. Add more salt, pepper, or lemon juice if needed. Stir gently again without breaking the chicken into very small pieces.

Cover the bowl with a lid or plastic wrap. Refrigerate the chicken salad for at least 30 minutes. This helps the flavors blend together and improves the taste.

Remove the salad from the refrigerator. Stir gently before serving. If the mixture feels too thick, add one tablespoon of mayonnaise or yogurt to refresh the texture.

Serve the chicken salad cold inside croissants, sandwiches, lettuce wraps, or with crackers. It also tastes wonderful over fresh lettuce for a healthy and filling meal.