Preheat your oven to 350°F (175°C). Grease and flour a 9x13 inch baking pan.
In a large mixing bowl, combine the chocolate cake mix, eggs, water, and vegetable oil. Whisk together until smooth and no lumps remain.
Pour the cake batter into the prepared pan and bake according to the package instructions, typically about 30-35 minutes, or until a toothpick inserted in the center comes out clean.
Once the cake is done, remove it from the oven and allow to cool in the pan for about 10 minutes.
Using the end of a wooden spoon or a straw, poke holes all over the top of the cake, about 1 inch apart.
In a mixing bowl, whisk together the sweetened condensed milk and caramel sauce. Pour this mixture evenly over the top of the cake, ensuring that the holes are filled.
Allow the cake to cool completely, then refrigerate for at least 2 hours or until ready to serve.
Just before serving, spread the whipped topping over the chilled cake.
Sprinkle the chocolate chips and toasted nuts on top for added crunch. Finish it off with a light sprinkle of sea salt to enhance the flavor.
Notes
Slice the cake into squares and drizzle extra caramel sauce over each piece before serving. Garnish with additional nuts or chocolate shavings for a luxurious touch.