Add 2 ½ cups chopped cooked chicken, 1 cup quartered grapes, 1 cup chopped pecans, ½ cup sliced green onions, ½ cup finely diced celery, 1 cup mayonnaise, 2 tablespoons lemon juice, and 1 tablespoon dijon mustard to a medium-sized bowl and stir until combined. Season with salt and ground black pepper to taste.
Serve on fresh croissants with romaine lettuce, or with crackers.