Avocado Waldorf Salad

I got this recipe from my sister. We made it last night for our BBQ dinner. It is very yummy, and quite sweet.

3 medium apples
1 large stalk celery, minced
1 T raisins or dried cranberries
1 recipe Avocado-Yogurt Dressing (see below)
1/4 c chopped walnuts

Cut apples into bite-sized chunks and add to medium bowl. Add celery and raisins or cranberries and toss. Add dressing and stir gently until everything is nicely coated. Serve topped with the walnuts.

Avocado-Yogurt Dressing
(Tip: the acid from the fruit juice helps the avocado stay green longer!)
1/4 c orange juice
1 T lemon juice
1 small avocado or 1/2 large one
1/2 c plain nonfat yogurt
1 T light-colored honey
pinch of salt
up to 1/2 tsp grated lemon or orange zest (optional)

Combine orange juice and lemon juice in medium sized bowl. Scoop out avocado and add to the juice. Mash with a fork until very smooth. Use a small wisk to beat in yogurt and honey. Add salt to taste, and some citrus zest if you like. Transfer to container with tight-fitting lid and chill until serving time.