Separate the egg yolks from the whites.

Using an electric mixer, beat the egg whites until stiff peaks form.

In a separate bowl, beat the egg yolks with the electric mixer.

Mix the dry ingredients together, then add the butter, apple cider vinegar, and water, continuing to stir with each addition.

Combine the egg yolks with the dry ingredient mixture.

Gently fold the beaten egg whites into the mixture.

Pour the mixture into a greased toast bread loaf pan and bake in the oven until fully cooked.

Remove the toast from the oven, let it cool slightly, then slice the toast into pieces.