Preheat oven to 350 degrees F. In a medium bowl, add the cake mix, water, vegetable oil and eggs. Beat with a hand mixer, on low speed for 2 minutes.
Grease a Texas-size muffin tin. (The Texas-size pans usually come in 6-cup pans) Fill each cup 2/3 full of cake batter. This recipe makes 9 cakes, so you will have leftover batter if you only have one pan. OR after the first batch is done baking, let pan cool then clean. Use remaining batter in 3 of the cups and bake.Bake for 25 to 30 minutes, or until toothpick inserted in center comes out clean.
Let cakes cool for 10 minutes in pan, then take a knife and loosen the edges. Carefully remove cakes from the pan, and place on a wire rack to cool completely.
Once cooled, take a knife and slice the ‘dome’ off the top of the cakes, so they are flat. Once the tops are flat, turn the cakes upside down. Using a sharp paring knife, cut out a 1-inch circle out of the center of the bottom (now the top) of each cake. The hole should be at least 1-inch deep. Scoop out the chunk of cake and discard. Repeat this process with all the cakes.
Warm the hot fudge in the microwave according to its directions. Spoon 2 Tablespoons of fudge into each of the holes in the cakes. Store the cakes in a sealed container in the freezer for at least 3 hours before serving.
When ready to serve, take one cake and place on a microwave-safe plate. Heat for 30 seconds. Remove from microwave and top with one big scoop of vanilla ice cream, then drizzle on Magic shell. Serve and enjoy!