This is basically an open faced eclair with a slight twist. A fairly light dessert that's pretty easy to make. It's called MOON pie because when the pate a choux is baked, in a sheet form for this, it has bumps & dips like the surface of the moon. Although I like going the homemade pastry cream & cocoa fudge icing route when I make eclairs & cream puffs; with this dessert I find it's best to use cook & serve vanilla pudding (or homemade pudding) because it sets better (so that when you start spreading on the top layer it doesn't mix in with it). I also use hot fudge ice cream topping instead because it's thicker and holds up better.
Preheat the oven to 400°F. Grease or spray with cooking spray (NOT the kind with flour added) a 15x11 inch jelly roll pan; set aside. In a medium saucepan, combine the water and butter; bring to a rolling boil (to evenly distribute the fats).
Add the flour and heat for an additional 2 minutes while stirring constantly with a wooden spoon. (the full mixture will form into a ball.) Place the heated mixture into a mixing bowl with paddle attachment. Mix at medium speed for about 2 to 3 minutes until most of the steam dissipates.
Add the eggs, one at a time, blending well & scraping the bowl after each addition at medium speed. The pate a choux should form a hook off the end of the paddle when it's turned upright, and should be smooth and shiny but not runny. Spread the pate a choux on the prepared pan (I use a greased large offset spatula). Bake for 20 to 25 minutes or until lightly golden brown. Remove from oven and cool in the pan on a wire rack.
Meanwhile, in a medium saucepan, stir together the milk and pudding mix and cook according to the box directions. Spread on the cooled crust and refrigerate until set.
In a mixing bowl, whisk together the cream cheese and whipped topping until well blended. Spread over the pudding layer.
Heat the hot fudge topping per the microwave instructions on the package. Drizzle over the top layer in a decorative design of your choice.
* I pour the heated hot fudge in a spouted bottle, draw horizontal lines 1/2" to 1" apart over the complete dessert, then drag a toothpick through the lines.