Recipe · Thailand · What Happens To The Leftover Roast Duck

Yum Ped Yang (ยำเป็ดย่าง)

Chinese roast duck — crisp skin, five-spice fat and all — tossed in the Thai hot-sour dressing of lime, fish sauce and chilli. The salad that gives the leftover duck a second life.

Yum Ped Yang — Thai spicy roast duck salad — sliced roast duck tossed with cucumber, onion and tomato in a chilli-lime dressing on a plate lined with lettuce

The Salad That Rescues The Leftover Duck

ยำเป็ดย่าง is a Thai-Chinese dish with a Thai-Chinese origin story. The Pantip cook whose thread opens the topic is explicit about hers: the roast duck came home from the Chinese New Year offerings — ไหว้ตรุษจีน — and after the shrine had had its share, the rest went into the salad. That is the dish's whole logic: Cantonese-style roast duck is glorious hot, but a day later it is greasy and stiff — and Thai cooks have the exact remedy for rich, leftover meat. The hot-sour dressing.

The duck itself is not Thai at all. เป็ดย่าง is the Chinese roast duck — lacquered skin, anise and cinnamon through the meat — the same duck that tops the noodle shops. What makes the dish Thai is what happens to it: the meat is tossed in น้ำยำ, the sharp dressing of lime juice, fish sauce and chilli that defines every ยำ, then lifted with raw vegetables. Duckking, the Thai roast duck chain, publishes the dish on its own recipe page as one of its เมนูแซ่บ — its hot-and-spicy list — with the dressing weighed to the gram. The home version below does the same job with a bottle of sweet chilli sauce and a squeeze of ketchup, the way two BlogGang home cooks wrote it in 2010.

The Recipe (home version, from the BlogGang diaries)

ThaiEnglishAmount
เป็ดย่างRoast duck, sliced bite-size300 g
แตงกวาCucumber, sliced2
หอมหัวใหญ่Onion, thinly sliced1
มะเขือเทศTomato, sliced1
ต้นหอมSpring onions, cut into lengths2
ผักชี + พริกชี้ฟ้าแดงCoriander and red spur chillies, for garnish2 stalks
ผักสดLettuce or salad greens, to line the plateas needed
The dressing (น้ำยำ)
พริกขี้หนูซอยBird's eye chillies, sliced2 tbsp
น้ำมะนาวLime juice4 tbsp
ผงปรุงรสไก่Chicken seasoning powder1 tsp
น้ำปลาFish sauce3 tbsp
ซอสพริกSweet chilli sauce2 tbsp
ซอสมะเขือเทศTomato ketchup2 tbsp
น้ำตาลทรายSugar1 tsp

The restaurant plate (Duckking): 120 g roast duck, 50 g onion, 50 g seeded tomato, 25 g spring onion, 25 g celery, with the dressing weighed at 45 g lime juice, 40 g fish sauce, 30 g sugar, 12 g chopped bird's eye chillies and 8 g chopped garlic — no ketchup, no sweet chilli sauce, and celery in the cucumber's place. Scale it up for the table. The leftover pot (Pantip): the New Year duck, deboned and seared in a pan until hot, dressed Isaan-style with lime, fish sauce, sugar, roasted rice powder (ข้าวคั่ว), shallots and coriander — the chilli left out because the cook's daughter does not eat hot food. The Lemon8 technique: warm the duck briefly and rest it before slicing, so it neither dries nor crumbles, and loosen the dressing with a spoon of the duck's own juices.

The Method

  1. The duck. Slice the roast duck into bite-size pieces. If it has come out of the fridge, Lemon8's rule applies: warm it gently first — a short microwave or air-fryer pass — and rest it a couple of minutes before slicing, so the meat stays moist and holds together in the dressing.
  2. The dressing. Stir the sliced bird's eye chillies, lime juice, chicken seasoning powder, fish sauce, sweet chilli sauce, ketchup and sugar together until the sugar dissolves. Taste it before it meets the duck — this is the whole dish's flavour, and it should read sour first, then salty, then hot, with the sweet tucked under.
  3. Duck first. Toss the duck with the dressing before anything else goes in. The meat soaks the dressing up; the vegetables are there to catch what's left.
  4. Vegetables last. Cucumber, onion, tomato, spring onion and coriander go in, and everything is tossed lightly — Lemon8 puts the tomato in last of all, because tomato is the first thing to weep water and flatten the dressing.
  5. Plate and correct. Taste once more, then plate on the lettuce leaves and finish with coriander and sliced red spur chillies. Every source agrees on the final step: it is made just before eating, while the lime is still bright and the vegetables still snap. Hot rice alongside, or eat it as drinking food with extra lime and chillies on the table.

Where Thai Sources Disagree

The dressing. Duckking is the purist: lime juice, fish sauce, sugar, chilli and garlic — a 45:40:30 ratio, weighed. The BlogGang home cooks add sweet chilli sauce, ketchup and chicken seasoning powder, which rounds the same balance off for a family table. Lemon8 keeps it to lime, fish sauce and a little sugar, with garlic optional, and stretches it with a spoon of the duck's own juices. Pantip dresses the duck Isaan-style — lime, fish sauce, sugar and roasted rice powder — and skips the chilli for the children.

The vegetables. Duckking: onion, seeded tomato, spring onion and celery — restaurant restraint. BlogGang: cucumber, onion, tomato, spring onion. Lemon8: cucumber, tomato, onion, carrot and coriander, with the onion soaked in cold water for five minutes first if it is strong. The cucumber question splits the sources straight down the middle.

Garlic. Duckking's dressing carries 8 g of chopped garlic. The BlogGang dressing has none at all. Lemon8 says a little garlic now and then, "to make it more fragrant". A matter of taste, and every version works.

How the duck is treated. Pantip debones the leftover duck and sears it in a pan until hot; Lemon8 warms it gently and rests it before slicing, so it neither dries out nor crumbles in the tossing; Duckking and BlogGang slice it straight from the roast. The first two agree on the principle — cold, fridge-hard duck does not belong in the salad.

The sugar. White sugar in Duckking, BlogGang and Pantip. Lemon8 allows palm sugar instead — the only source that does. All four keep it small: the sweet chilli sauce and the duck itself are already sweet.

How Western Versions Get It Wrong

UK Ingredient Notes

Sources

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

1. BlogGang — "ยำเป็ดย่าง" by tongsehowgolf (the home recipe used here) — bloggang.com

2. Duckking — "ยำเป็ดย่าง" (the roast duck chain's published restaurant recipe, weighed to the gram) — duckking.co.th

3. Lemon8 — "วิธีทำยำอกเป็ดย่าง รสจัดจ้าน เปรี้ยวเผ็ดครบ ใส่แตงกวา-มะเขือเทศ" (the warming, slicing and duck-juice techniques) — lemon8-app.com

4. Pantip — "น้ำตกเป็ดย่าง" topic 36073668 (the post-Chinese-New-Year leftovers story; the Isaan rice-powder version) — pantip.com

5. BlogGang — "ยำเป็ดย่าง" by somkitjar (the same home recipe in a second diary) — bloggang.com

Johnny Tiger
Johnny researches and translates Thai recipes from Thai-language sources — chefs, restaurants and home cooks in Thailand — and publishes them with their sources cited. No westernised shortcuts, no invented steps.