Prepare the Crust:
Place the Oreos in a food processor and pulse until they are finely crushed.
Add melted butter to the crushed Oreos and mix until well combined.
Press the mixture into the bottom of a 9×13-inch baking dish to form the crust. Refrigerate while you prepare the filling.

Make the Filling:
In a large bowl, beat the softened cream cheese until smooth.
Add the instant vanilla pudding mix and milk, and beat until the mixture thickens, about 2 minutes.
Stir in the caramel sauce until fully combined. Set aside.

Prepare the Topping:
In a large mixing bowl, beat the heavy whipping cream with powdered sugar and vanilla extract until stiff peaks form.

Assemble the Lasagna:
Spread half of the vanilla pudding mixture over the Oreo crust.
Drizzle 1/2 cup of caramel sauce and 1/2 cup of hot fudge sauce over the pudding.
Sprinkle with half of the chopped pecans.
Spread half of the whipped cream over the pecans, smoothing it out evenly.
Repeat with another layer of the pudding mixture, caramel and fudge sauces, chopped pecans, and whipped cream.
For the final layer, top with the remaining whipped cream and decorate with optional turtle candies and a drizzle of caramel and fudge sauce.

Chill:
Cover the dish with plastic wrap and refrigerate for at least 4 hours or overnight for the lasagna to set.