Preheat oven to 350 degrees. Put chicken breasts in a baking dish, sprinkle with olive oil, salt & pepper and bake in the oven for 35-45 minutes or until skin is lightly browned and juices run clear. Allow to cool.
Meanwhile, add the shredded carrot and chopped celery to a large bowl with 2 tsp of dill and the toasted walnuts. Mix well. Set aside.
In a small bowl combine the Greek yogurt, mayo, 2 tbsp chopped dill and lemon juice. Mix well. Add salt & pepper to taste.
Recipe by FEASTS AND FOTOS at https://www.feastsandfotos.com/2009/05/13/chicken-salad/