Soften gelatin in 1/2 cup water in a small saucepan. Cook over low heat, stirring constantly, until smooth and thickened. Add bouillon granules, salt, pepper, and Worcestershire sauce, stirring until granules are dissolved. Remove from heat; add remaining water and onion, stirring well. Chill until the consistency of unbeaten egg whites. Gently stir in chicken, celery, olives, pimiento, and parsley. Fold in whipped cream; spoon into a lightly oiled 4-cup mold. Cover, and chill overnight. Sprinkle with paprika, if desired. Serve with crackers.