Ingredients: duck eggs, white wine, salt.
Step:
1. Wash the duck eggs, dry them with a cloth, and put them into a basin;
2. Pour proper amount of white wine into the basin, soak the duck eggs for two hours, and take them out;
3. When the surface of duck eggs is not completely dry, coat them with a thick layer of salt;
4. Put fresh-keeping film on the surface of duck eggs;
5. Put it in a cool place for one month to make oil, and then boil it.