from rose's celebrations by rose levy beranbaum:
mix 2 8oz pkgs cream cheese, 1/4c. mayo, 1/3c. grated parm, 2tbsp finely chopped onion, 1 tsp grated horseradish, 2 tbsps each finely chopped carrot and celery, 1/2 tsp salt. place on plastic wrap, form into ball, put in small bowl to help hold shape, fridge at least 1 hr, roll in chopped, toasted walnuts if desire, serve with crackers. yummy.