In a large bowl, combine the water, vanilla instant pudding mix, sweetened condensed milk, and molasses. Whisk until smooth. Cover with plastic wrap and transfer to the fridge for at least 4 hours, or overnight.
Once the mixture has chilled, add the heavy cream to a large bowl and whip until stiff peaks have formed. Add 1/3 of the whipped cream to the bowl with the pudding. Gently fold it in. Add the remaining whipped cream to the bowl and mix until smooth.
Either in a large bowl or several cups, layer the pudding -- add a layer of the pudding mixture, then top with some sliced bananas, then some gingerbread cookies. Repeat until all the pudding is used.
Place in the fridge for 30 minutes to chill. Enjoy!!