Waldorf Chicken Salad

Looking for a light recipe for a Sunday night I decided to make a salad that I haven't made in many years. The Waldorf Salad was created in 1893 at the Waldorf Astoria Hotel in NYC.  This recipe was adapted from Southern Living and took only 20 minutes to put together.  Based on reviews I modified it slightly, as written below, by adding one more apple and cutting the honey mustard from 1/2 cup in the original recipe to 1/4 cup.  This ratio was perfect.  I packed a container for my work lunch tomorrow!

1/2 cup chopped walnuts
3 cups diced cooked chicken (I bought plain "Just Chicken" at Trader Joe's)
1 cup seedless red grapes, halved
2 large Gala apples, diced leaving skin on
1 cup diced celery
1/2 mayonnaise
1/4 cup honey mustard (Koop's brand) 

Preheat oven to 350 degrees.  Bake walnuts in a single layer in a shallow pan
6 - 8 minutes or until toasted and fragrant, stirring halfway through.

Stir together chicken, next 5 ingredients and walnuts.  Add salt and pepper to taste.