Preheat the oven to 180°C and grease a loaf pan approximately 23×13 cm.

In a mixing bowl, combine the mashed bananas with sugar, vegetable oil, almond milk, and almond flour.

In another bowl, mix the flour with baking powder, baking soda, salt, and cinnamon if using.

Fold the dry ingredients into the wet ingredients, being careful not to overmix. Add the walnuts and quickly stir to incorporate evenly.

Pour the mixture into the loaf pan and bake for 50-60 minutes, or until a knife inserted in the center comes out clean. Allow to cool in the pan for 10 minutes, then transfer to a wire rack to cool completely before serving.