In a shallow dish, whisk together the egg whites, protein powder, almond milk, cinnamon, and vanilla extract until well combined.

Preheat a non-stick skillet or griddle over medium heat and lightly coat with cooking spray.

Submerge each slice of bread into the egg mixture, allowing it to soak for approximately 20 seconds on each side.

Place the soaked bread onto the hot skillet and cook for 3 to 4 minutes per side, or until golden brown and the center is set.

Transfer to a plate and serve warm.