Preheat your oven to 350°F (175°C). Grease a 9-inch round cake pan and line with parchment paper.
In a mixing bowl, whisk together flour, cocoa powder, baking soda, baking powder, and salt.
In a separate large mixing bowl, combine sugar, eggs, milk, vegetable oil, and vanilla extract. Mixwell using an electric mixer or whisk.
Gradually add the dry ingredients to the wet ingredients, mixing until just combined.
Carefully pour boiling water into the batter, stirring gently until smooth. The batter will be thin.
Pour the batter into the prepared cake pan and bake for 35-40 minutes, or until a toothpick inserted in the center comes out clean.
Remove the cake from the oven and let it cool in the pan for 10 minutes before transferring it to a cooling rack. Allow the cake to cool completely.
Once the cake has cooled, spread the chocolate frosting evenly over the top and sides of the cake.
Decorate the cake with edible decorations, such as fondant figures of Max and Ruby, carrots, or other elements related to the show.
Serve the cake with a scoop of ice cream or a dollop of whipped cream, if desired.