Grease baking pan with a little bit of the margarine.
Mix the rest of the margarine with sugar and 1 whole egg until mixture is unified.
Gradually and alternately add: flour, cocoa, 1 whole egg, pudding, flour, cocoa, apple sauce, pudding -- and so on, until all mixes up nicely to a homogeneous mixture.
Pure into greased baking pan (square or round) and bake for about 30 minutes, or until cake is ready: dry and bouncy to touch.
When the cake is ready I take it out of the oven and cover-seal it with aluminum foil until cools. This ensures the crust keeps moist.
To decorate, I use chocolate syrup, usually Hershey's (w/0g fat)- and spread it all over as if it was frosting. It's good enough for the sprinkles to stick, and it adds additional moist and chocolaty flavor.
*** You may substitute the dairy pudding with soy pudding to make this cake Pareve.