In a high-speed blender, combine the liquid egg whites, Greek yogurt, oat flour, baking powder, cinnamon, sea salt, and vanilla extract.
Blend on high for 30 seconds until the batter is completely smooth and slightly aerated.
Peel the banana and slice it into thin, uniform rounds.
Heat a large non-stick skillet over medium-low heat and add the coconut oil, swirling to coat the surface.
Pour the batter into the skillet to form four medium-sized pancakes.
Quickly press 3-4 banana slices into the wet top of each pancake before the batter sets.
Cook for 3-4 minutes until bubbles form on the surface and the edges look dry.
Carefully flip each pancake and cook for another 2 minutes, allowing the banana slices to caramelize against the hot pan until golden brown.
Remove the pancakes from the heat and stack them on a plate.
Drizzle the maple syrup over the warm stack and serve immediately.