Preheat a grill to medium-high heat. Coat a 10-inch cast-iron skillet with nonstick cooking spray.
Stir together the cream cheese and marshmallow cream in a large bowl until well combined. Spoon one-third of the cream cheese mixture into the skillet and spread into an even layer. Top with half the candy bar pieces, one-third of the crushed graham crackers and one-third of the marshmallows.
Spoon half of the remaining cream cheese mixture over the marshmallows and spread into an even layer. Top with the remaining candy bar pieces, half of the remaining crushed graham crackers and half of the remaining marshmallows. Spoon the remaining cream cheese mixture over the marshmallows and spread into an even layer. Top with the remaining marshmallows and crushed graham crackers. Sprinkle with the peanuts.
Place the skillet on the grill and close the lid. Cook until the center of the mixture is hot and gooey, about 20 minutes. Drizzle with the chocolate fudge and caramel toppings and serve with graham crackers.
If you don't have a grill or prefer to make this inside, you can bake the mixture in the oven at 400 degrees F for the same amount of time.