In a blender, put one raw egg, a teaspoon of mustard, salt/pepper and a half of a cup of sauerkraut. Blend on high. Then start adding mild vegetable oil - like avocado oil - in a thin stream with the blender running until mayo thickens. Keep in the fridge for up to a week.
Watch Video by Nadia Ernestus - Our 'Kraut Queen'