In a large mixing bowl, crack one whole egg and add ¼ cup of Greek yogurt. If desired, sprinkle in ½ teaspoon of ground cinnamon and pour in ½ teaspoon of vanilla extract. Whisk these ingredients until smooth and creamy, ensuring there are no lumps. Next, add ⅓ cup of your chosen protein powder followed by ¼ cup of milk. Whisk again until the custard is lump-free, adjusting with extra milk if the mixture feels too thick.

Take your slices of whole-grain or gluten-free bread and prepare to dip them in the custard. Submerge each slice for about 30 seconds on each side, ensuring it's fully soaked for optimal flavor and texture.

Heat a non-stick skillet over medium heat and lightly grease it with cooking spray or a small knob of butter. Once hot, carefully place the soaked bread slices in the skillet. Cook for 2–3 minutes on one side until golden brown and crispy, then flip and cook the other side for an additional 2–3 minutes.

Once cooked, transfer your Protein French Toast slices onto a warm plate. Top with Greek yogurt, sliced bananas, or a drizzle of maple syrup if desired.