Preheat the oven to 350°F. Prep three 9 inch round baking pans with parchment cut to fit the bottom. Grease the sides, bottom and top of the parchment with cooking spray oil.
In a large mixing bowl, whisk together the dry ingredients for the cake. Slowly stir in the wet ingredients until there are no lumps or dry patches. Be sure to scrape the bottom and sides of the bowl as your stir.
Pour the cake batter into the prepared baking pans. Bake for 30-35 minutes, or until a toothpick inserted into the center of each cake comes out clean. Remove the cakes from the oven and cool in the pans until the cakes are room temperature.
Cover the cakes lightly with plastic wrap then transfer to the freezer. Freeze the cakes for 24 hours - or up to a week in advance. DO NOT SKIP FREEZING THE CAKES.
Up to 5-6 hours before serving, make the ganache. In a sauce pan over medium heat, heat the heavy cream until just steaming but not bubbling hot. Pour the hot cream over the chocolate chips in a large bowl. Stir until the chocolate chips are completely melted and the chocolate is glossy.
Cool the ganache to room temperature, stirring every 15-20 minutes until the ganache reaches a spreadable, frosting-like consistency.
Level the tops of two layers of cake so that they are flat. Place one cake on a cake stand and spread the ganache from edge to edge and over the sides as a crumb coat. Place the next layer on top and repeat with the remaining ganache. Finally, place the last layer on top and fill in the gaps around the layers with the ganache. Chill for one hour.
About an hour prior to serving, use the fudge frosting to frost the cake from top to bottom in a swirling motion to mimick what is seen in the movie. Chill for at least thirty minutes prior to serving to fully set the frosting. Serve to an unwilling elementary school child and enjoy!