Preheat oven to 400 degrees F.

Whisk together water, egg whites, and apple cider vinegar.

Slowly add the mix, while whisking. Whisk briskly as it thickens. Once mixed, allow to rest a minute.

With damp hands, knead the dough together then shape into an oblong loaf that will fit in the bread pan.

Bake on the center rack in the oven for 1 hour 15 minutes. Cover loosely with aluminum foil for the last 15-20 minutes if the bread gets too brown.

Cool in pan for 5 minutes. If necessary, run a knife around the sides of the pan to loosen the bread.

Using oven mitts, transfer the loaf to cool on a rack.