Red Bean Soup (红豆汤), Two Ways: Warm or Chilled

If mung bean soup is the light, cooling side of summer, red bean soup is its cozier cousin — thicker, rounder, a little more comforting. Made from small adzuki beans simmered down with a little rock sugar, hóng dòu tāng is one of the most beloved sweet soups in Chinese homes, and one of the most versatile: warm and soothing in winter, or chilled and refreshing in summer. It even freezes into excellent popsicles.

It's a forgiving, hands-off recipe — mostly a matter of letting the beans simmer until they soften and turn creamy. There's just one thing worth knowing up front, because it's where most people go wrong: getting the beans tender.

The one trick: getting the beans soft

Adzuki beans are stubborn. Cooked straight from dry, they can take well over an hour and still come out chalky. Two easy fixes:

• Soak them first. A few hours (or overnight) in cool water shortens the cooking time a lot and helps them cook evenly.
• Or use the rest-and-return method. Bring them to a boil, simmer 30 minutes, turn off the heat, cover, and let them sit for 30 minutes. The residual heat softens them from the inside, then you return to a simmer. Many home cooks swear this gives the creamiest result.

Either way, only add the sugar after the beans are soft — adding it too early can keep the beans firm.

Ingredients

Makes about 4–6 servings

• 200g (about 1 cup) dried adzuki / red beans (红豆)
• 60–80g rock sugar (冰糖), to taste
• About 1.5–2 liters (6–8 cups) water
• Optional: a small piece of dried tangerine peel (陈皮) for a subtle fragrant lift

How to make it

1. Soak. Rinse the beans and soak them in cool water for at least a few hours, ideally overnight. Drain.

2. Simmer. Add the beans to a pot with the water (and the tangerine peel, if using). Bring to a boil, then lower to a steady simmer.

3. Cook until soft. Let it simmer, partly covered, for about 45–60 minutes, until the beans are fully tender and beginning to break apart. Stir now and then, and top up with a little water if it gets too low. For a thicker, creamier soup, mash some of the beans against the side of the pot or simmer a little longer.

4. Sweeten. Once the beans are soft, stir in the rock sugar until dissolved. Taste and adjust — it should be gently sweet, letting the nutty bean flavor come through.

5. Serve warm, or chill. Enjoy it warm as a cozy bowl, or let it cool and refrigerate for at least 2–3 hours to serve cold in summer.

Tips

• Warm or chilled — your call. This soup genuinely shines both ways. Cozy and hot when it's cool out; cold from the fridge when it's hot.
• Make popsicles. Pour the sweetened soup (slightly on the thinner side) into molds and freeze for a simple, satisfying frozen treat.
• Add tangerine peel. A small piece of dried tangerine peel (陈皮) adds a lovely fragrant, slightly citrusy note that cuts the richness — a classic pairing worth trying.
• Keeps well. Stored in the fridge it holds for 3–4 days and thickens as it sits; loosen with a splash of water when reheating.

Building your sweet soup pantry

Adzuki beans are a cheap, shelf-stable staple worth keeping all summer. If you're stocking a Chinese sweet-soup pantry from scratch, the Pantry page lists the ingredients and tools I use and recommend.

Looking for more? Try its lighter cousin, the classic sweet mung bean soup, the cooling snow fungus soup with pear, or the cozy black sesame soup.

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