In a bowl, mash up the bananas with a fork.
Add in eggs and whisk until combined.
Add in Greek yogurt and oil. Whisk until combined.
Add in brown sugar, baking soda, salt, cinnamon and vanilla. Whisk until combined.
Add in flour, and fold in with a spatula until no more dry flour spots.
Transfer mixture into a parchment lined loaf pan. Bake at 325°F for 45-50 minutes, until a golden brown and a toothpick comes out with no wet batter on it.
All to cool for at least 30 minutes before slicing.