Preheat your oven to 350°F (175°C). Lightly grease and flour a 9x13 inch baking pan, or spray with non-stick baking spray.

In a large mixer bowl, combine the all-purpose flour, granulated sugar, cocoa powder, baking soda, baking powder, and salt. Mix briefly and set aside.

In a separate medium-sized bowl, whisk together the milk, vegetable oil, vanilla extract, and large eggs until well combined.

Add the wet ingredients mixture to the dry ingredients in the mixer bowl. Beat on medium speed until just combined. Scrape down the sides of the bowl as needed.

Slowly pour the hot water into the batter while mixing on low speed until the batter is smooth and all ingredients are incorporated. Do not overmix.

Pour the prepared cake batter into your greased 9x13 inch cake pan.

Bake for 29-32 minutes, or until a toothpick inserted into the center of the cake comes out with a few moist crumbs.

Remove the cake from the oven. While it's still warm, use the end of a wooden spoon, a straw, or a similar round object to poke holes all over the top of the cake, making sure not to go all the way to the bottom of the pan.

In a large measuring cup or bowl, combine the sweetened condensed milk and caramel sauce. Whisk until smooth.

Slowly and evenly pour the caramel-milk mixture over the poked cake, allowing it to seep into the holes. Let the cake cool completely in the pan, either at room temperature or in the refrigerator.

To make the peanut butter whipped cream topping, add the cold heavy whipping cream, powdered sugar, peanut butter, and vanilla extract to a large mixer bowl.

Whip on high speed until stiff peaks form and the topping is light and fluffy.

Once the cake is completely cooled, spread the peanut butter whipped cream evenly over the top.

Garnish the cake with chopped chocolate peanut butter candy bars. Drizzle with additional caramel sauce and chocolate sauce, if desired.

Refrigerate the cake for at least 30 minutes before serving to allow the topping to set.