In a large mixing bowl, add the softened cream cheese. Beat it with a spoon or hand mixer until smooth and creamy.
Add mayonnaise and Dijon mustard to the cream cheese. Stir until well combined.
Fold in the cooked chicken, celery, green onions, grapes, and nuts (if using). Mix until evenly coated.
Add salt, pepper, and any fresh herbs to taste. Adjust seasoning as needed.
For best flavor, cover and refrigerate for 30 minutes before serving.
Serve on croissants, sandwiches, lettuce wraps, or with crackers.