Grease a 12 muffin tin. Preheat oven to 375.

Mix melted butter, sugar, vanilla and milk together in a mixing bowl.

Mash in the bananas to the wet mixture using a fork, do not use a mixer. Using super ripe bananas is key to ensure the muffins are nice and moist. My bananas were basically black on the outside.

Sift in flour, baking soda and cinnamon. Mix together using a large spoon. Using a mixer will over mix the batter.

Add batter to the prepared muffin tin. Filling about 1/2 way. Bake in the oven for 20 minutes. In the last 5 minutes I turned the oven to 400 to ensure a nice brown top.

Take out and cool on a cooling rack for 5 minutes and enjoy!