In a large bowl, mash the bananas.
Add the vanilla extract. Mix.
Add the oatmeal, the milk and the oil. Mix it all. Then add the Nutella and mix again. Let it on the counter for about 15 minutes. Pre-heat oven at 350 faranheit.
On a stick-free plate, divide in 9 bars and place in the oven at 350 faranheit for 20 minutes.