Mix condensed milk with cold water until it dissolves.
Pour in the instant vanilla pudding into the milk until it thickens.
Chill in the fridge for at least 4 hours. (Don't forget to cover).
After four hours, whip the heavy cream to peak.
Pour in the pudding into the cream, fold and mix evenly. Texture should be smooth.
Chill in the fridge for another 4 hours (or not, if you can't wait :P)
Use individual crystal cup or ramekin - and spread a little of the pudding in the bottom.
Alternately layer banana slices and wafers - with pudding in between each.
Repeat and end with pudding on top.
Garnish with a sprinkle of wafers, nuts, and grated chocolate.