1Heat oven to 275°F. Grease bottom and sides of 13x9-inch pan. In large bowl, beat egg whites, cream of tartar and salt with electric mixer on high speed until foamy. Beat in 1 3/4 cups sugar, 1 tablespoon at a time; continue beating until stiff and glossy. Do not underbeat. Spread in pan.
2Bake 1 hour. Turn off oven; leave meringue in oven with door closed 12 hours.
3In large bowl, mix cream cheese, 1 cup sugar and the vanilla until smooth. In chilled medium bowl, beat whipping cream until stiff. Fold whipped cream and marshmallows into cream cheese mixture. Spread evenly over meringue. Refrigerate at least 12 hours but no longer than 24 hours.
4In medium bowl, mix all topping ingredients until well blended. Spoon over individual servings of dessert. Store in refrigerator.