If you know what tau suan is, you probably know that 'tau' ('豆') means beans. What about 'suan'? What does 'suan' mean?
No one has ever explained to me the meaning of 'suan'. But I know that when 豆爽 is made with lotus seeds instead of mung/green beans, it's called 蓮子爽. And my mother made a savory sticky soup with chicken and duck 'spare parts' – gizzards, livers, blood and intestines – called 爽腹內. So '爽' probably means sticky soup, which could be savory or sweet. Kind of like '羹', I guess.
Cooking for the President has an alternative explanation that's quite interesting. The Nyonya Hokkien author says 'suan' means diamonds because the little beans in tau suan look like diamonds, and 'diamonds' ('钻') in Hokkien (and Teochew) is pronounced 'suan'.
Diamonds, eh? Make mine lotus seeds size please! Actually . . . mung bean size would do too. Give me a handful, just a small handful 'cause I'm not greedy.
'豆钻' miswritten as '豆爽'? Oh dear, how embarrassing!
Fortunately, Nyonyas aren't exactly a world authority when it comes to the Chinese language. It's '豆爽' on China websites, which presumably have a higher standard of Chinese than a Peranakan Chinese. Shucks, there goes my diamonds!
|TAU SUAN (豆爽, SPLIT GREEN BEAN SWEET SOUP)|
(Recipe for 8 persons)
220 g split mung/green beans (1 cup)
4 pandan leaves, lower/light green part only, wash and cut 8 cm (3 inches) long
200 g sugar (1 cup)
6 cups water
16 pandan leaves, wash and knot
⅔ cup sweet potato flour (White Swallow brand, special grade), mix with ⅓ cup water
. . . if you use other brands, you may need to sieve the flour if it doesn't dissolve well
. . . because it's coarse
1 pair 油条 (you char kway, Chinese crullers), divorced
. . . toast till crisp just before serving, then snip crosswise 1½ cm thick with scissors
Soak mung beans in water till expanded, about 1 hour. Drain thoroughly. Lightly oil a plate or line with parchment paper. Spread evenly with half of beans. Place cut pandan leaves on beans, spaced evenly. Top with remaining beans. Steam over rapidly boiling water till cooked but not mushy, 10 minutes or so. Remove from heat. Discard pandan leaves. Set aside till ready to serve. Cover only after beans are cool.
Place sugar in a pot. Drizzle with 2 tbsp water. Cook over medium-high heat, swirling to ensure even browning. When sugar is lightly coloured, reduce heat to medium-low. Continue swirling till sugar is light brown, then turn off heat. Keep swirling till sugar is medium brown (like honey that's not too dark). With your hand to the side of the pot (to avoid the burst of steam), add 6 cups water. Turn on heat and bring to a boil. Add knotted pandan leaves and simmer gently, covered, for 10 minutes. Discard leaves. Taste and adjust sweetness if necessary. Set aside till ready to serve.
To serve, bring pandan sweet soup to a boil. Add mung beans. Once soup returns to a gentle simmer, stir and, at the same time, drizzle with sweet potato flour slurry. Bring back to a gentle simmer. Turn off heat immediately. Do not overcook or beans would turn mushy. Stirring too much and cooking after the soup has thickened would make it watery.
Serve tau suan hot, topped with you char kway just before eating.