Heat the broth to a boil in a 2-quart saucepan over medium-high heat. Stir in the rice and lentils. Reduce the heat to low. Cover and cook for 20 minutes or until done. Let stand for 5 minutes or until the liquid is absorbed.
Toss the lentil mixture, parsley, ground red pepper, celery, onion, green pepper and vinaigrette in large bowl until evenly coated. Cover and refrigerate for at least 2 hours or overnight. Serve on the lettuce.