In a large mixing bowl, whisk together the oat flour, whey protein powder, baking powder, cinnamon, and salt until evenly combined.
In a separate bowl, whisk together the liquid egg whites, almond milk, and vanilla extract.
Pour the wet ingredients into the dry ingredients and fold gently with a spatula until just combined; do not overmix to preserve aeration.
Preheat a non-stick griddle or skillet over medium-low heat and lightly coat with cooking spray.
Pour 1/4 cup portions of batter onto the griddle.
Cook for 2 to 3 minutes until bubbles form on the surface and edges appear set.
Flip carefully and cook for an additional 1 to 2 minutes until golden brown and cooked through.