century egg; preserved egg
A Chinese delicacy made by preserving duck, chicken, or quail eggs in a mixture of clay, ash, salt, quicklime, and rice hulls for several weeks to months.
from Chinese pídàn
I bought some century eggs in Chinatown.
Century eggs are delicious when added to rice porridge.
Borrowed from Chinese 皮蛋 (pídàn), literally 'skin egg' or 'leather egg', referring to the preserved egg's appearance.