In a mixing bowl, mix together the protein powder, flour, baking powder, and salt.

Pour in the water, egg whites, and yogurt. Stir well to combine.

If your batter feels too thick, slowly add more liquid until it reaches a smooth, creamy texture.

Preheat your waffle iron and grease it generously.

Pour the batter into the center of the preheated iron and cook until golden brown, about 3 minutes.

Re-grease the waffle iron between batches.

Transfer cooked waffles to a plate and serve immediately with toppings.