In A Small Bowl, Beat The Cream Cheese, Peanut Butter, Brown Sugar And Vanilla Until Smooth; Stir In Marshmallows. Spoon Half Into A 3-Cup Bowl; Spread With Half Of The Hot Fudge Topping. Repeat Layers. Sprinkle With Nuts. Toss The Apples With Lemon Juice. Serve Immediately With Dip.