Soak the dried yellow fungus in cold water for several hours or overnight until plump and soft. Drain, trim the woody base, and tear into bite-size florets.

Peel the chestnuts (simmer in boiling water briefly to loosen skins if fresh). Cut pumpkin into even bite-size chunks. Pit the red dates and rinse the sweet jujube dates.

Bring the water with the ginger slices to a gentle boil, then add the yellow fungus, chestnuts and pumpkin and return to a simmer.

Add the red dates and sweet jujube dates, lower the heat to a steady soft bubble, and simmer uncovered for about 40 minutes, skimming any foam, until the fungus is silky and the broth glossy.

Sweeten to taste with rock sugar if desired, then ladle into warm bowls and enjoy hot, or chill and serve cold.