For the crust: Preheat the oven to 340 degrees F. Break up the cookies into small pieces and press into a 9-by-9-inch baking pan. Brush with melted butter. Bake for 11 minutes.
For the peanut butter fudge: Put the confectioners' sugar in a large mixing bowl and set aside. Melt the butter in a small saucepan over medium heat. Stir in the brown sugar, whipping cream and salt. Bring to a boil. Boil for 2 minutes and remove from the heat. Stir in the peanut butter and vanilla. Pour the mixture over the confectioners' sugar and mix. Spoon the mixture into the cookie pie crust until it is completely covered.
For the caramel: In a small saucepan, combine the heavy cream, brown sugar, granulated sugar, corn syrup, whipping cream, butter and salt. Heat over low heat until the butter is completely melted. Gradually increase the heat to medium-high and bring the mixture to a boil, stirring frequently. Reduce the heat to medium and continue to boil, while stirring, until the temperature on a candy thermometer reads 250 degrees F. Remove from the heat, stir in the vanilla and pour over the peanut butter fudge. (You can double the recipe for this layer and pour half of the caramel into a buttered dish to cut up and enjoy as caramel candies.)
For the marshmallows: In a microwave-safe bowl, melt the marshmallows in the microwave for 40 seconds. Working quickly, use a spatula to spread over the caramel layer. If you take too long, the marshmallows will set up and won't spread nicely.
For the chocolate fudge: Put the confectioners' sugar in a large mixing bowl and set aside. Melt the butter in a small saucepan over medium heat. Stir in the cream, brown sugar and salt. Bring to a boil. Boil for 2 minutes and remove from the heat. Stir in the chocolate and vanilla until all the chocolate is melted and the mixture is smooth. Pour the mixture over the confectioners' sugar. Beat with an electric mixer for 3 to 4 minutes until very smooth. Spread evenly over the marshmallow layer with a spatula.
For the toffee: Sprinkle the toffee over the top of the chocolate fudge.
To serve: You do not have to wait for the fudge to set before serving. Using a metal spatula, cut and serve in cake-like squares.
This recipe was provided by a chef, restaurant or culinary professional and may have been scaled down from a bulk recipe. The Food Network Kitchens chefs have not tested this recipe, in the proportions indicated, and therefore, we cannot make any representation as to the results.