Preheat your oven to 350°F (175°C) and lightly grease a mini loaf pan with a small amount of avocado oil or parchment paper.
In a medium mixing bowl, mash the half banana until it reaches a smooth, liquid-like consistency with minimal lumps.
Whisk in the liquid egg whites and vanilla extract until the mixture is well combined and slightly frothy.
Add the almond flour, vanilla protein powder, chia seeds, baking powder, cinnamon, and sea salt to the wet ingredients.
Stir the batter gently until all dry ingredients are fully incorporated, being careful not to overmix.
Pour the batter into the prepared mini loaf pan, smoothing the top with a spatula.
Bake for 25 to 30 minutes, or until the top is golden brown and a toothpick inserted into the center comes out clean.
Allow the loaf to cool in the pan for 10 minutes before transferring to a wire rack to cool completely before slicing.