1. Shred the lettuce and place in a salad bowl. Halve, core and cut the apples into triangles or cubes, cutting and reserving a few slices for garnish. Chop the celery.
2. Mix together the apples, celery, walnuts, yogurt, sugar, mustard and seasoning and turn into the salad bowl on top of the lettuce. Top with a walnut and apple slices and serve to accompany cold meats.
Nuts add texture interest as well as flavour to salads. Used in adequate proportions they also provide protein to make a main dish. Try hazelnuts, pecans, brazils, peanuts and almonds in salads.