Preheat the oven to 350°F (175°C) and spray a 9x13 inch cake pan with cooking spray.

In a large bowl, stir the chocolate fudge cake mix, pudding mix, milk, vegetable oil, and eggs together until fully combined.

Pour the prepared cake batter into the 9x13 inch cake pan and bake in the oven for 30-35 minutes or until a toothpick comes out clean in the center.

Remove the cake from the oven and use the bottom of a chopstick or wooden spoon to poke holes throughout the cake, about 2/3 of the way down.

Allow the cake to cool for 20-30 minutes.

Once cooled, pour the sweetened condensed milk over the cake, ensuring it pools in the poked holes.

Pour 1/2 cup of the divided caramel sauce over the condensed milk.

Gently spread the whipped topping over the top of the cooled cake into an even layer.

Drizzle the rest of the caramel sauce across the whipped topping and sprinkle the toffee bits and chopped chocolate on top.

Place the cake, uncovered, in the refrigerator for 1 hour to cool completely.

Cut the cake into generous squares and plate with a drizzle of extra caramel, a flake of sea salt, or a spoonful of espresso.

Serve cold to ensure the whipped topping holds its shape.