The original Waldorf salad, is a mix of diced apples and celery tossed in a good-quality mayonnaise.
Photo Credit Andrew Scrivani for The New York Times
1 medium ripe apple
1 stalk celery, chopped
¼ cup mayonnaise
Salt and pepper
2 cups lettuce, torn into bite-size pieces
Peel apple and cut into halves. Remove core and slice halves 1/4-inch thick. Reserve 4 slices. Cut remaining slices into thin strips.
In a medium bowl, mix celery, mayonnaise and apple strips; season with salt and pepper to taste. Arrange on lettuce and top with apple slices.
Later versions of the salad commonly added chopped walnuts. If you'd like, toss 1/4 cup of them in with the celery and apple.