In a medium bowl, mix together Quest Protein Powder®, egg whites, oat flour, almond flour, wheat gluten, butter, baking powder, and salt.
Once combined, form a dough ball with your hands and gently knead a few times.
Form into a small 5-by-2-inch loaf, and place on a parchment-lined baking sheet. Bake for 14 to 15 minutes. Move to a cooling rack and cool for 10 minutes.
Slice loaf into twelve thin slices, and lay on a nonstick baking sheet. Bake for 5 minutes.
Flip bread slices and bake for an additional 5 to 7 minutes, or until crisp.