Shred the cooled cooked chicken into bite-sized pieces in a large mixing bowl. Mix in the finely chopped onions and diced dill pickles.

In a separate bowl, whisk together the Greek yogurt and mayonnaise until smooth. Add the optional relish, Dijon mustard, chopped chives, fresh dill, and a sprinkle of salt and pepper. Mix thoroughly.

Pour the creamy dressing over the chicken and vegetable mixture. Gently fold the dressing into the chicken until evenly coated.

Taste your salad and adjust seasoning if necessary. Ensure the flavors are balanced before chilling.

Cover the bowl with plastic wrap or transfer to an airtight container and refrigerate for at least 2 hours, preferably overnight.

Serve the salad, giving it a gentle stir. Enjoy it on croissants, over greens, or as a dip with crackers.