200 gm green mung beans
2 sprigs rue/stink grass (臭草)
8 pieces seaweed
50 gm rice
2 liters water
rock sugar, to taste
Rinse the beans and soak for about 1 hour. Soak the seaweed until softened. Drain well. Cut into thick strips. Rinse rice and drain well. Set aside.
Use a large deep pot. Add 2 liters of water and bring to boil. Add the beans, rice and stink grass. Cook over high heat. When it boils, reduce heat to medium-low and simmer until the beans are soft. Keep an eye on it while cooking because you don’t want the soup to spill over everywhere.
Add the seaweed and rock sugar to taste, continue to cook until the sugar completely dissolves. Done. Served hot, warm or cold.

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50 grams (1/3 cup) small sago (small tapioca pearls)
100 grams green beans (aka mung beans/lu dou/綠豆) soaked overnight, rinsed and drained
2 pandan (screw pine) tied in a knot
1.7 litres water
10 grams (or 3 small pieces) dried orange/tangerine peel (陈皮)
80 grams canned or vacuum-packed lotus seeds or ginkgo nuts optional
70 grams rock sugar (冰糖) to taste
Bring a small pot of water to boil. Add sago and simmer for 10 minutes. Turn off the stove, cover the pot with lid and let the sago continue to cook on its own for another 10 minutes, until all the sago turns translucent. Run the cooked sago through a fine sieve and running water to remove excess starch. Set aside. Check out this step-by-step photo tutorial for preparing sago.
In a bigger soup pot, add green beans, pandan leaves, water and orange peel. Bring to a boil.
Add lotus seeds/gingko nuts and reduce heat to a simmer, partially covered, for about 50 minutes (or until the beans are soft), stirring the sides and bottom of the pot occasionally. Top up with hot water at any time if needed.
Stir in rock sugar until the sugar is dissolved. Discard orange peel slices and pandan leaves. Add the cooked sago prepared in step 1 to the green bean soup. Serve warmed or chilled.