Preheat your oven to 350°F (175°C) and grease two 9-inch round cake pans.
In a large mixing bowl, combine flour, sugar, cocoa, baking powder, baking soda, and salt.
Add eggs, milk, oil, and vanilla. Beat on medium speed for 2 minutes.
Stir in boiling water until the batter is smooth; it will be thin.
Pour the batter evenly into prepared pans.
Bake for 30-35 minutes or until a toothpick comes out clean.
Let the cakes cool in the pans for 10 minutes, then remove from pans to cool completely.
Once cooled, slice each cake in half horizontally to create four layers.
Spread a layer of frosting on the first layer, drizzle with caramel, and sprinkle with peanuts.
Repeat for the remaining layers and top with chocolate frosting and additional peanuts.