Preheat your oven to 350ºF and spray a 9x13 cake pan with baking spray.
Start by making the chocolate cake. Whisk the chocolate cake mix, water, eggs and oil in a large bowl until smooth.
1 box (15.25 ounces) chocolate cake mix, 1 cup water, 3 eggs, 1/2 cup vegetable oil
Pour the chocolate cake batter into the prepared cake pan and spread it evenly. Bake the cake for about 30 minutes. The cake will spring back to the touch and a toothpick inserted in the center of the cake will come out cleanly. Let the cake cool in the pan.
Once the cake has cooled, use your finger or the round handle of a wooden spoon to poke holes across the entire cake, making a small hole every 1-2 inches.
Mix the sweetened condensed milk and caramel sauce in a medium sized bowl. Pour the mix over the entire cake, letting it soak into the holes.
1 (14 ounce) can sweetened condensed milk, 1 cup caramel sauce
In a large mixing bowl, whisk the heavy cream, powdered sugar and vanilla extract until the mix forms stiff peaks. Spread the whipped cream over the entire cake, making a nice and even layer.
1 1/2 cups heavy cream, 1/4 cup powdered sugar, 1 teaspoon vanilla extract
Sprinkle the chopped Snickers bars and peanuts across the top of the cake then drizzle with the chocolate sauce and extra caramel sauce.
2 full-sized Snickers bars, 1/2 cup dry roasted, salted peanuts, chocolate sauce, caramel sauce
Serve the cake immediately or refrigerate until you are ready to enjoy a slice!