traditional chicken salad recipe

Ingredients: 2 cups cooked chicken, diced or shredded (leftover roast chicken or poached chicken breast works well) 1/2 cup mayonnaise 1/4 cup celery, finely chopped 1/4 cup red onion, finely chopped 1/4 cup grapes, halved (optional, for a touch of sweetness) 2 tablespoons fresh parsley, chopped 1 tablespoon lemon juice 1 teaspoon Dijon mustard Salt and freshly ground black pepper to taste Optional: 1/4 cup chopped pecans or almonds