Place couscous and salt in a stainless steel or glass mixing bowl. Place chicken stock and apple juice in a small saucepan and heat to a rolling boil. Alternately, place chicken stock and apple juice in a microwave safe container and microwave on high until boiling rapidly. Pour boiling liquid over couscous. Cover bowl with plastic wrap and let stand 5 minutes or until all liquid is absorbed. Remove plastic wrap and fluff couscous with two forks. Spread couscous on a baking sheet and place in refrigerator to cool completely.
Combine remaining salad ingredients. Taste and season with salt and pepper. When couscous is cold, combine with mixed salad ingredients. Add dressing and toss to coat thoroughly