Step 1: Bake the Cake

Preheat oven to 350°F (175°C).

Grease a 9×13-inch baking dish.

In a large mixing bowl, combine the devil’s food cake mix, water, vegetable oil, and eggs.

Beat according to cake mix package directions until smooth.

Pour the batter evenly into the prepared baking dish.

Bake according to package instructions, until a toothpick inserted in the center comes out clean.

Remove the cake from the oven and place it on a wire rack.

Step 2: Poke and Fill

While the cake is still warm, use the handle of a wooden spoon to poke holes evenly across the entire surface of the cake.

In a small bowl, stir together the sweetened condensed milk and half of the caramel topping.

Slowly pour the mixture over the cake, making sure it seeps into the holes.

Allow the cake to cool completely so the filling fully absorbs.

Step 3: Add the Toppings

Once cooled, spread the remaining caramel topping evenly over the cake.

Sprinkle the chopped chocolate-covered toffee bars evenly across the surface.

Gently spread the thawed whipped topping over the entire cake in an even layer.

Step 4: Chill

Refrigerate the cake for at least 2 hours, or until well chilled and set.

Slice and serve cold for best texture and flavor.