Grate half of the apple and thinly slice the remaining half for a fresh garnish.
In a large bowl, whisk together the egg whites, Greek yogurt, and vanilla extract until well combined.
Add the vanilla protein powder, oat flour, cinnamon, baking powder, and sea salt, stirring until a smooth batter forms.
Fold the grated apple into the pancake batter.
Lightly coat a non-stick skillet with coconut oil and place over medium heat.
Pour the batter into the skillet to form three large pancakes, cooking until small bubbles appear on the surface.
Carefully flip each pancake and cook until the edges are golden brown and the center is set.
Serve immediately topped with the reserved apple slices.