In a large pan, add the condensed milk and vanilla.
In a bowl, whisk the whole milk and eggs until blended. Add the ingredients to the pot and whisk together.
Heat for about 10 minutes on low heat stirring occasionally.
Add the ground Nilla wafers to the pan and whisk.
Heat stirring occasionally until pudding-like consistency forms (about 15-20 minutes).
Remove the pudding from the heat and allow to cool for about 10 minutes.
In a baking dish, layer the bottom with Nilla wafers.
Then add a layer of sliced bananas.
Pour about half of the pudding over the bananas and Nilla wafers (Just enough to cover them).
Add an additional layer of bananas then Nilla wafers.
Pour the remaining pudding over the Nilla wafers.
Add an additional layer of Nilla wafers on top of the dish.
Cover and refrigerate overnight (24 hours recommended).