Preheat oven to 350 degrees.
Combine cake mix, instant pudding and sugar in large bowl. Blend with a whisk to break up lumps. Add next four ingredients and mix with mixer on low speed to combine ingredients. Scrape down sides of bowl and continue to mix on high for about 2 minutes.
Spray jumbo muffin pan with cooking spray and fill each muffin well about half full of mixture. Bake until toothpick inserted comes out clean. This will make about 12 to 14 individual jumbo cup cakes. Let cakes cool.
While cakes are baking, combine the chocolate sauce ingredients: mix the cocoa with sugar, add melted margarine and evaporated milk. Stir to mix and cook until mixture begins to boil. Lower temperature and cook for 5 minutes. Let cool.
When cakes have cooled, hollow out center of each cake and fill with chocolate sauce. (Use hollowed out portion as snacks if desired.) Put cakes in a covered container and place in the freezer. When ready to eat, take cakes out of the freezer and microwave each one individually for 45 seconds. Place a scoop of vanilla ice cream on top and drizzle with the remaining chocolate sauce, or you may use chocolate Magic Shell ice cream topping for a crunchy coating.