Yam Tua Pu (ยำถั่วพู)

The Bean with Four Wings

ถั่วพู is the winged bean, cut crossways its pods show four frilly wings, and Thais treat it as a salad vegetable first — the star of ครัวบ้านพิม's menu, who wrote her 2011 ยำถั่วพูกุ้งสด post because her mother arrived from the family orchard in Chanthaburi with a bag of beans and a reminder not to let them sit. The other classic uses — ไข่เจียวถั่วพู omelette, แกงส้ม sour curry — all lean on the same property: a pod that stays crisp through heat if you treat it right.

The dish is a stack of textures. The beans are blanched barely — Wongnai's brand recipe times it at one minute exactly, ครัวบ้านพิม watches for the water to come back to the boil, tukata001 on Pantip says "a moment only" — then shocked in iced water. Around them: sweet blanched shrimp, blanched minced pork, and a dressing of น้ำพริกเผา (roasted chilli paste), fish sauce, lime and palm sugar, rounded with coconut cream. On top goes the fried layer — shallots, garlic, dried bird's eye chillies — and usually a soft-boiled egg.

tukata001's recipe exists because she ordered a version from a yam shop and got shrimp blanched to mush in a sickly-sweet dressing — the note under her recipe reads like a manifesto: make it yourself, pack the garnishes on, and season it properly. Everyone who publishes the dish agrees on the non-negotiable: the beans must crunch, and the ice bath is how you guarantee it.

The Recipe (home version, from ครัวบ้านพิม)

The brand batch (Wongnai, กะทิเรียลไทย): 200 g beans, 100 g shrimp, 100 g pork, 1 egg — dressing of 2 tbsp fish sauce, 3 tbsp lime juice, 1½ tbsp palm sugar, 1 tbsp nam phrik phao, and only 2 tbsp coconut cream, simmered until it splits and drizzled at the end. The loaded bowl (tukata001): 3 tbsp each of white sugar, fish sauce and lime juice, plus pounded garlic and chillies, 5 tbsp fresh coconut cream stirred raw into the dressing, and a garnish line-up of toasted coconut, pounded dried shrimp, cashews and fried dried shrimp (see the disagreement below). The vegetarian bowl (Food News & Life): fried tofu and shimeji mushrooms replace the meat, vegetarian nam phrik phao and light soy in the dressing.

The Method

1. The proteins. Blanch the shrimp in fiercely boiling water until they change colour and lift out. Same pot, back to the boil: add the minced pork and break it apart with the spatula until cooked, then drain. ครัวบ้านพิม keeps the pork water in the pot for the next job.
2. The beans. Trim both ends, pull the side strings, slice on the diagonal about 1.5 cm. Soak a moment in salted water so they don't blacken, drain, then into hard-boiling water — ครัวบ้านพิม presses them under with the ladle and covers the pot. The moment it re-boils, uncover; cook to your liking, then straight into very cold water. Wongnai's version oils the water instead of salting it; both agree the ice shock is the crunch guarantee.
3. The fried layer. Fry sliced garlic to golden, drain; then sliced shallots to golden, drain. Wongnai's traditional recipe salts the shallots before frying — the salt draws the water out and they crisp better. Roast the peanuts and pound them rough.
4. The dressing. Nam phrik phao, fresh chillies, fish sauce, lime juice and palm sugar in the mixing bowl; stir until the sugar dissolves, then add 5 tablespoons of coconut cream. Taste now — tukata001's rule is to season before the beans go in, because once they're in you can't fix it.
5. The toss. Shrimp, pork and beans through the dressing. Plate with the boiled egg, scatter the fried chillies, fried shallots, fried garlic and peanuts, and drizzle the last 2 tablespoons of coconut cream over the top. Serve immediately — the crunch has a half-life.

Where Thai Sources Disagree

How Western Versions Get It Wrong

• Green beans instead of winged beans, cooked to softness. The winged bean's frilly edges and hollow crunch are the dish. Whatever bean you substitute, the blanch-and-shock is not optional — a soft bean turns yam tua pu into a wilted slaw.
• Dressing it like a vinaigrette. There is no oil in the dressing. Fish sauce, lime, palm sugar and nam phrik phao do the work; olive oil does not belong anywhere near this bowl.
• Omitting nam phrik phao, or swapping in sriracha. The roasted-chilli-in-oil paste is what rounds the sharpness. Sriracha gives heat and sugar and none of the smoke.
• Using canned coconut milk instead of coconut cream. The Thai recipes distinguish them on purpose: the drizzle needs cream — rich enough to split, or thick enough to bind the dressing. Light coconut milk waters the salad down.
• Skipping the fried layer. Fried shallots, fried garlic and fried dried chillies are not decoration; they are the second texture. A yam tua pu with raw shallots and no crunch layer is a different, sadder salad.

UK Ingredient Notes

• Winged beans (ถั่วพู): fresh at Thai and Vietnamese grocers in season, frozen at some — call ahead. The closest supermarket stand-in is fine French beans; they lack the frilly wings but keep the crunch if you shave the blanch down.
• Nam phrik phao (น้ำพริกเผา): jars of roasted chilli paste at any Thai grocer — Mae Pranom and Pantai are the common brands; pick one that isn't too sweet, as the recipes specify.
• Coconut cream: the solid block or the thick top of a full-fat coconut milk tin; not light milk. Fresh squeezed from grated coconut is what ครัวบ้านพิม recommends if you can get grated coconut.
• Palm sugar (น้ำตาลปี๊บ): Thai grocers and mainstream supermarket world-food aisles.
• Dried bird's eye chillies and fresh bird's eye chillies: Thai grocers for the dried ones; fresh ones are now standard in UK supermarkets.
• Roasted peanuts, fish sauce, limes: no specialist trip needed.

Sources

This recipe is translated from the following Thai-language sources. Where they disagree, we've said so.