Fill the pan with water, cover, and simmer very gently over the lowest heat possible for at least 6 hours, even overnight. A layer of oil poured over the surface is a good way of preventing the water from evaporating too quickly. This lengthy cooking produces deliciously creamy eggs. The whites acquire a soft beige color from the onion skins, and the yolks are very creamy and pale yellow. The flavor is delicate and excitingly different from eggs cooked in any other way.
Some people add ground coffee to the water, to obtain a slightly darker color.
Serve hamine eggs as an appetizer over a dish of ful medames , or as a garnish for meat stews.