Pulse the rolled oats in a high-speed blender until they reach a fine, flour-like consistency.
In a medium mixing bowl, whisk together the oat flour, vanilla protein powder, baking powder, cinnamon, and sea salt.
Add the egg whites and Greek yogurt to the dry ingredients, stirring until a smooth batter forms, then let it rest for 2 minutes to thicken.
Slice the half banana into even rounds.
Heat a large non-stick skillet over medium-low heat and melt half of the ghee.
Ladle the batter into the skillet to form 3 or 4 pancakes, cooking until bubbles appear on the surface and the edges look set.
Flip the pancakes carefully and cook for another 1-2 minutes until golden brown, then remove from the pan.
Add the remaining ghee and the maple syrup to the same skillet, then place the banana slices in the pan.
Sauté the bananas for 1 minute per side until they are soft and caramelized, then spoon them over the warm pancakes to serve.