Pre-heat oven to 350 degrees F.
Melt margarine, stir in Oreo crumbs and sugar. Press firmly into a sprayed 11 x 7 pan. I know this is an odd size but 9 x 13 is too large and your dessert layers will be too skinny. 9 x 9 would be fine as well.
Bake for 10 to 15 minutes and cool completely.
In a saucepan mix together evaporated milk, 1 % milk, baking chocolate and pudding mix. Cook on medium low until bubbling and thickened - I make sure I cook this for 10 minutes on low, stirring with a wire whisk constantly.
Remove from heat and stir in vanilla extract.
Cover with sprayed plastic wrap (this will prevent a tough skin from forming) and leave on the counter until room temperature.
When cooled, whisk again just to smooth it up and spread carefully over cooled crust.
Cover again with plastic wrap and refrigerate until firm.
Whip cream with a packet of Dr. Oetker's whipping cream stabilzer and spread over fully cooled pudding - decorate with nuts or toasted coconut.
VARIATIONS: Are endless! I have made the above version with 2 layers: chocolate cooked pudding AND coconut cooked pudding. Another is chocolate AND banana cooked puddings. You can substitute the Oreo crumbs for graham crumbs and use vanilla or butterscotch puddings instead - omit the square of baking chocolate in these cases.