Preheat your oven to 350°F (175°C). This ensures that the bread bakes evenly and rises beautifully.
Grease your loaf pan with a bit of butter or line it with parchment paper for easy removal after baking.
In a large mixing bowl, whip the 6 large egg whites using a whisk or electric mixer until soft peaks form.
In another bowl, whisk together the 2 egg yolks, 1 cup of yogurt, and 1/2 cup of melted butter until smooth.
In a separate bowl, sift together the coconut flour, whey protein powder, baking powder, and a pinch of salt.
Gently fold the dry mixture into the wet mixture using a spatula until just combined.
Pour in the 2 tablespoons of lukewarm water and fold it into the batter.
Carefully fold the whipped egg whites into the batter in three additions.
Transfer the batter to your prepared loaf pan, smoothing the top with a spatula.
Bake in the preheated oven for 30-35 minutes, or until golden brown and a toothpick inserted into the center comes out clean.
Once baked, remove the bread from the oven and let it cool in the pan for about 10 minutes before transferring it to a cooling rack.
