Preheat the oven & line pan: Preheat oven to 180ºC (356ºF). Grease with butter a round 8-inch baking pan and line with baking paper, set aside. NOTE: Alternatively, if you have a quality non-stick pan, liberally grease it with melted butter and dust it with a light layer of flour. This will leave your finished cake with smooth sides.
Mix dry ingredients: In a large mixing bowl, add flour, baking powder, and baking soda. Whisk together until well combined.
Add sugar: Add sugar and whisk until well combined.
Mash the bananas: Peel bananas and mash in a bowl with a fork or potato masher.
Combine wet ingredients: Add in mashed banana, milk, oil, vinegar, and vanilla. Gently fold with a spatula until well combined, ensuring not to over-mix, just ensure there are no large pockets of flour remaining in the batter.
Pour into pan: Pour batter into the prepared baking pan. Smoothing out the top.
Bake the cake: Transfer to oven and bake for 40-45 minutes, until a toothpick inserted into the middle comes out clean and it’s lightly golden on top and looks set.
Cool: Remove from the oven and allow the cake to cool in the pan for 15 minutes. Transfer to a wire rack to cool completely.
Brush with syrup: Once cooled, pour maple syrup into a small bowl and take a pastry brush and brush a layer or desired amount of syrup over the cake. Serve and enjoy!