Blend the oats into a fine flour if you want smoother pancakes; skip blending for a bit more chew.
In a bowl, mash the banana and whisk it with the eggs, milk, and vanilla until smooth.
Add the oat flour, protein powder, baking powder, cinnamon, and salt. Mix until just combined, thick but pourable.
Heat a nonstick pan over medium heat and lightly grease it with butter or oil.
Pour about ¼ cup of batter per pancake and spread it out slightly.
Cook until bubbles form and the edges start to set, about 2–3 minutes.
Flip and cook the other side for another 1–2 minutes until golden brown.
Keep the pancakes warm under a towel or foil while you cook the rest.