Bake cake per instructions on back of cake mix box using a 9 x 13 baking dish. (NOTE: I substituted milk instead of water, brought eggs to room temperature, and substituted butter for the oil, to give it more of a bakery style fluffy cake.)
Cool cake completely in baking dish on a wire rack.
In a stand mixer bowl place shortening and butter. Cream together for 2-3 minutes until combined. Add in sugar, vanilla, and evaporated milk. Beat on setting 2 or 4 for 8-10 minutes until light and creamy. Spread filling over cooled cake evenly.
Place chocolate fudge frosting In a microwave safe bowl. Melt in microwave for 10 seconds, stir, place back in microwave and melt another 10 seconds, stir and place in microwave once more for 10 seconds until frosting is pourable.
Pour or spoon melted frosting over the filling layer and spread evenly. (NOTE: Frosting will set pretty fast so spread the frosting quickly.)
Let sit at room temperature for 2-3 hours to allow the frosting and filling to set up. Or place in refrigerator for 1 hour to set up faster. Enjoy.
