1. Wash the yam, cut into sections, steamed in a pot, and peeled.
2. Add appropriate amount of salt, pepper, and oil to make a puree.
3. Separate the egg whites and yolks, put them in a bowl, and add appropriate amounts of salt, pepper, wet starch, and oil to each.
4. Take a mold and spread it with plastic wrap, and then put the yam puree into it and smooth it out.
5. Pour in the egg yolk and steam for 13 minutes.
6. Open the lid, pour in the egg white liquid, and steam for another 13 minutes.
7. Take out and let cool, pour out and cut into pieces.
8. Plate.
