Khanom Buang
“Crisp folded crepelets the size of a child's palm — a wafer-thin rice-and-mung-bean shell topped with meringue cream and either sweet shredded coconut with foi thong egg-yolk threads, or salted shrimp with cilantro.”
Where it comes from
Khanom Buang is documented in Ayutthaya-era court manuscripts (17th century) as a refined sweet served at temple ceremonies. The egg-yolk thread topping foi thong descends from Portuguese fios de ovos, brought to Siam in the 17th century by the half-Japanese, half-Portuguese cook Maria Guyomar de Pinha at the court of King Narai. Street vendors adopted simplified versions in the 19th and 20th centuries, and modern Bangkok stalls still distinguish the salted-shrimp version (older, indigenous) from the sweet version (the court-Portuguese hybrid).
On the plate
Each bite is the size of two fingers, almost weightless. The shell shatters between your teeth into rice-paper shards; underneath, the meringue is soft and faintly almond-scented from the egg whites. Sweet version is a layered hit — coconut chew, then the lacquered sweetness of foi thong threads. Salty version reads almost like a savoury cracker: shrimp umami pushed forward by sugar. A khanom buang that bends instead of snaps has been sitting too long — the shell needs to be fresh-eaten.
How it works
Mung-bean flour is what makes the shell shatter rather than bend — its high amylose content gelatinises into a brittle film, where pure rice flour would stay leathery. Lime water (nam pun sai) raises the pH and crisps the texture further. Critically the griddle is held at 160°C: hot enough to set, cool enough not to brown. Browning would push the shell toward toffee chew. The meringue layer is structural — it stops moisture from the toppings reaching the shell and softening it.
Documented in 17th-century Ayutthaya court manuscripts. The egg-yolk thread foi thong topping descends from Portuguese fios de ovos, brought to Siam by Maria Guyomar de Pinha at King Narai's court.
Variations
Salty version (older, indigenous) uses dried shrimp and pepper — found in older Bangkok markets; sweet version with foi thong is the court-Portuguese hybrid; modern fusion stalls use fruit and sweetened cream.
On the Palate
Ingredients
Serves 6
How it's made
6 steps · Show ↓50 min active · 10 min waiting
How it's made
6 steps · Show ↓- 114 min
Toast 50g hulled mung beans dry in a wok 4 minutes until faintly aromatic. Grind to a fine powder. Combine with 100g rice flour, 30g tapioca starch, 1 tbsp lime water (nam pun sai), pinch salt. Whisk in 220ml water to a thin pourable batter. Rest 10 minutes.
- 210 min
Whip 2 egg whites with 80g caster sugar to firm peaks. Sweet topping: simmer 100g grated young coconut with 50g palm sugar and 20ml water 4 minutes until sticky; cool. Salty topping: mix 80g dried shrimp floss with 40g grated coconut, 30g sugar, 1 tbsp fish sauce, then dry-toast 3 minutes.
- 32 min
Heat a flat griddle (or non-stick skillet) to 160°C — lower than you'd think. Wipe with the merest film of oil. Drag a small ladle of batter across the surface in one swipe to leave a 10cm wafer-thin smear, almost translucent.
Watch outEnsure the oil is just a film; too much will cause the shell to fry instead of cook evenly.
- 42 min
Cook 90 seconds — the shell should dry from translucent to matte and lift cleanly at the edges, never browning. If it browns, the heat is too high.
Watch outMonitor closely; if the edges brown, reduce the heat immediately.
- 52 min
Pipe a 3cm stripe of meringue down the centre. Spoon either coconut topping with foi thong threads, or salty shrimp with cilantro leaves, on top of the meringue.
- 62 min
Lift one edge with a spatula and fold the shell into a half-moon — it should curl crisp and brittle. Slide off the griddle. Eat within 30 minutes; the shell goes soft once humidity sets in.
Watch outServe immediately to maintain crispness; humidity will soften the shell quickly.
What you'll need
A carbon-steel hemispherical pan, 30-40 cm across, with a rounded bottom and high sloping walls. The bottom takes ferocious direct heat — a properly seasoned wok over a roaring gas flame holds 250-300°C, hot enough to deliver wok hei, the breath-of-the-wok smoky char prized in Cantonese stir-fry. The sloped walls give cooler zones for batch-cooking, and the rounded bottom lets a single tossing motion distribute oil and food evenly.
A heavy, single-piece cast iron pan, 25-30 cm across, weighing 1.5-2.5 kg. Once preheated, the thick mass holds 230°C+ even when a cold steak hits the surface — that's the secret to a deep crust. A well-seasoned skillet (multiple thin layers of polymerized oil baked into the iron) is essentially nonstick, gets better with use, and lasts a century. Lodge skillets from Tennessee have been in continuous production since 1896.
