Red Bean Soup (Hong Dou Tang / 红豆汤)

Ingredients

• 300 g dried azuki (red) beans, soaked overnight in cold water, drained
• 1.5 litres water
• 80 g rock sugar (bing tang), broken into small pieces
• 1 piece dried tangerine peel (chen pi), aged 3+ years preferred; soaked briefly in warm water until pliable
• Optional additions
• 50 g dried lotus seeds, soaked and bitter green core removed
• 50 g dried lily bulb (bai he), soaked until softened

Method

1. 1
   Drain the soaked beans and place them in a heavy pot with the water and the softened tangerine peel. Bring to the boil over medium-high heat, then reduce immediately to a gentle simmer. The surface should tremble rather than roll.
2. 2
   If using lotus seeds or lily bulb, add them now. Continue to simmer, partially covered, for 60–90 minutes. This is where the dish lives or dies: the heat must remain a low, steady simmer throughout — vigorous boiling will burst the beans and reduce them to paste rather than leaving them soft and intact. Check periodically that the liquid is barely moving.
3. 3
   When a bean pressed between two fingers yields completely but holds its shape without collapsing, the beans are done. Add the rock sugar and stir gently until fully dissolved.
4. 4
   Taste for sweetness; adjust with a little more rock sugar if required. Remove and discard the tangerine peel. The soup should taste gently earthy-sweet with a clean citrus aromatic note in the background — not cloying, not flat.
5. 5
   Serve hot in winter or allow to cool fully and refrigerate to serve chilled in summer. Ladle into bowls; the broth should be a deep garnet-red, opaque but not thick.