Two dumplings can be cut from the same wrapper and stuffed from the same bowl of filling, and one comes out of the pot whole while the other opens into the soup.
What separates them is invisible once they are cooked: how much water was left in the filling, and whether the centre of the fold was pressed shut. The institute’s standard recipe and the recipe card below both come back to those two things.
Where mandu first shows up in Korean records
The Encyclopedia of Korean Culture says mandu came from China at a time nobody can pin down, but the Goryeosa, the official history of Goryeo, records a punishment for people who stole mandu from the royal kitchen under King Chunghye, so the dish was already in Korea by the Goryeo period. The same entry points to a Goryeo song, Ssanghwajeom, whose title means the ssanghwa shop, and suggests that the word ssanghwa may be a borrowed name for mandu.
The sources differ on what the song’s ssanghwa was. The Encyclopedia of Korean Culture reads it as a steamed dough with a filling, cooked the way Chinese mandu is. The Folk Encyclopedia calls the ssanghwa-byeong of that song a bun with no filling that reached the peninsula in the Yuan era. It adds that Chinese buns had already split into filled and unfilled kinds from the twelfth century, and that ssanghwa in Goryeo and Joseon texts comes in both forms. Both entries agree on a Goryeo arrival, and the song’s recipe is left open here.
In Joseon the vocabulary shifted. The Encyclopedia of Korean Culture says that by the mid-Joseon period the leavened bun had come to be called ssanghwa and the filled dumpling had taken the name mandu, and that the bun has since vanished, so only the filled one keeps the name.
Names that tell you how the seal will be tested
The standard dictionary defines mandu as flour dough wrapped around a filling and boiled, steamed or fried, sometimes put in rice cake soup or made into a soup of its own. The definition also lists gyoza and pozi as synonyms. The names on a menu follow the same logic, and each one hints at what the fold will have to survive.
Boiled, steamed and fried
The Encyclopedia of Korean Culture sorts mandu by how they are served: dumplings simmered in hot broth are mandu-guk, steamed ones eaten without liquid are jjin-mandu, and dumplings in chilled broth are pyeonsu. The Folk Encyclopedia adds that Koreans call Chinese-style wonton and boiled dumplings mul-mandu. The institute’s mandu-guk page notes that the same dumplings can be steamed or pan-fried, the fried kind being gun-mandu.
Fillings and shapes
The same entry lists wrappers of wheat, buckwheat or fish, and fillings such as squash, meat, mushroom and kimchi. Triangular byeonssi-mandu, sea-cucumber-shaped gyuasang and a large mandu made of several small ones are old shapes. The institute’s standard-recipe page names kimchi, chive, spinach, shrimp and meat as the usual ways to fill, and adds that wrappers taste best when they are as thin as possible.
Court crescents, Kaesong pockets and Joseon buckwheat
The Encyclopedia of Korean Culture says mandu served on festive and ritual tables and as a winter seasonal food, and that they developed in Pyeongan and Hamgyeong provinces in the north, where buckwheat and wheat were grown. Court and yangban kitchens made delicate kinds such as eomandu (fish mandu) and gyuasang, which were hard to make, and the pyeonsu of Kaesong is still famous as a local dish.
The Folk Encyclopedia fills in the Joseon method. Because wheat was not widely grown, cooks made wrappers by scalding buckwheat flour with mung bean starch, as the cookbook Eumsik dimibang describes, and filled them with radish and minced pheasant or beef, then served them in a soy and vinegar dip with ginger juice. In the palace, says the Folk Encyclopedia’s entry on mandu-guk, the wrapper was folded into a smooth half-moon without pleats, and that shape was also called byeongsi. The Folk Encyclopedia adds that northern families who moved south kept folding mandu on New Year’s Day into the late 1990s.
The institute’s wrapper and filling, by weight
The Korea Food Promotion Institute’s standard recipe is written for four servings and spells out both parts. It is longer than the card, but its numbers give a useful baseline.
A wrapper of 360 g flour, rolled to 3 mm
The wrapper is 3 cups of flour (360 g), 1 and a half cups of water and a teaspoon of salt, kneaded and covered with a damp cloth for 30 minutes, then rolled to about 0.3 cm and cut into 8 cm rounds. A floured surface keeps the rounds from sticking. If store-bought wrappers are used, the first two steps are skipped, and the page suggests about 50 frozen sheets.
A filling that has been wrung out
The filling is 150 g of minced beef in a light marinade, a block of tofu (300 g) squeezed dry in a cloth, 200 g of mung bean sprouts blanched for 3 minutes and chopped to about 0.3 cm, and 100 g of chives cut the same size, with scallion, garlic, sesame oil and salt. Everything is worked together by hand. The pattern is the same as the card’s: wet ingredients are squeezed before they meet the meat.
The recipe card makes about 30 dumplings from 300 g of ground pork and 200 g of tofu pressed under a weight for 15 minutes. It adds 300 g of napa cabbage salted for 10 minutes and squeezed dry, and 100 g of bean sprouts blanched for only 1 minute, and leaves out chives. It also admits that this drying step decides whether the filling stays put or turns the wrappers to mush.
The fold that closes the centre first
The institute folds each round into a half-moon over a spoonful of filling after wetting the edge, and presses the edge hard enough that no air is trapped. It notes that other shapes are possible. The card works at the same job, with more detail about order, and puts the weight on one point: do not overfill. It calls overfilling the single most common reason mandu split open, and asks for about one level tablespoon of filling per wrapper.
Wet the edge, then press the centre point
On the card, half the wrapper’s edge is dampened with a fingertip, the wrapper is folded over the filling, and the centre point is pressed firmly shut before anything else. A seam left open in the middle is the likeliest place for steam or water to push through.
Pleat one side only
From the centre, small pleats are pinched along one side of the seam and pressed against the flat opposite edge, three to five pleats per side. The goal in the card’s words is a sealed edge with no flat gaps, not an even fan. Finished mandu go onto a floured tray without touching, and the wrappers and dumplings waiting their turn stay under a damp towel.
Three ways to cook them, and what each asks of the seal
The card gives a time for each method. Steaming takes 10 to 12 minutes in a lined basket with space between the pieces. Pan-frying is two stages: the bottoms fry for 2 minutes, then 3 tablespoons of water go in and the pan is covered at once for 4 to 5 minutes. Boiling means dropping them into gently simmering water or broth for 6 to 8 minutes, until they float and the wrapper looks translucent. The institute steams its dumplings for 20 minutes, and for mandu-guk it calls them done when they rise to the surface.
Boiling asks the most of the seal, since the dumplings move under water. The card’s call for gently simmering water or broth fits that, and a hard boil would knock the dumplings against each other.
Korean Mandu
Ingredients
Method
- Press the tofu between paper towels with a weight on top for 15 minutes, then crumble it. Salt the chopped cabbage, let it sit 10 minutes, then squeeze out as much water as you can with your hands. This step decides whether your filling stays put or turns your wrappers to mush.
- Combine the pork, tofu, cabbage, bean sprouts, glass noodles, scallions, garlic, ginger, soy sauce, sesame oil, salt and pepper in a large bowl. Mix by hand until evenly combined and slightly sticky.
- Lay a wrapper flat and spoon about 1 tablespoon of filling into the center. Resist the urge to add more — overfilling is the single most common reason mandu split open.
- Wet the edge of the wrapper halfway around with a fingertip dipped in water.
- Fold the wrapper in half over the filling to form a half-moon, pressing the center point firmly to seal first.
- Working from the center outward, pinch small pleats along one side of the seam only, pressing each pleat against the flat opposite edge as you go. Three to five pleats per side is normal; the goal is a sealed edge with no flat gaps, not a perfectly even fan.
- Set each finished dumpling down on a floured tray, not touching the others, and keep the rest covered with a damp towel while you work.
- To steam: place in a lined steamer basket with space between pieces, steam 10 to 12 minutes over boiling water. To pan-fry: heat oil in a skillet, fry the bottoms 2 minutes until golden, add 3 tbsp water, cover immediately and steam 4 to 5 minutes. To boil: drop into gently simmering water or broth and cook 6 to 8 minutes, until they float and the wrapper looks translucent.
Recipe card photo: Korean cuisine-Jjinmandu-01.jpg by egg (Hong, Yun Seon), CC BY 2.0, via Wikimedia Commons.
When bought wrappers are the sensible shortcut
The card is written around a pack of about 30 round dumpling wrappers, and the institute names the same shortcut at about 50 frozen sheets for its four servings. Folding 30 dumplings still takes time (the card gives 40 minutes of prep), but bought wrappers remove the rolling and cutting and leave the part that matters, the filling and the seal.
The dip is quick. The institute mixes 2 tablespoons of soy sauce, 2 of vinegar, 1 of water and a teaspoon of chili flakes. The card uses 2 tablespoons of soy sauce, 1 of rice vinegar, a teaspoon of sesame oil, a pinch of chili flakes and chopped scallion. Both follow the soy-and-vinegar pattern the Folk Encyclopedia records for Joseon mandu, and the same pattern, thinned or thickened, runs through how thick and thin soy dips differ.
How mandu-guk is built
The institute’s mandu-guk page shows the soup form. A smaller wrapper of 1 cup of flour is rolled and cut into 8 cm rounds, filled with beef, shiitake, tofu, bean sprouts and chopped kimchi (squeezed of its juice), and shaped either as a half-moon or like a baby’s cap. The dumplings go into 2 litres of beef stock over medium heat and are done when they float, and the bowl gets strips of yellow and white egg.
Kimchi in the filling links the soup to the stew built on aged kimchi, and the institute squeezes it before it goes in, the same drying logic as the tofu. The other flour soup to compare is a soup where the dough is torn, not sealed, with no filling and no seam to fail.
What makes a mandu split open in the pot?
Between the card and the institute, three causes come up. The first is water left in the filling, from cabbage, tofu or sprouts that were not squeezed; the card says this step decides whether the filling stays put or turns the wrappers to mush, and the institute wrings out its tofu and sprouts too. The second is overfilling, which the card puts first among reasons for splitting. The third is a seal that was never closed at the centre, or an edge pressed without care, which the institute warns against when it says to press the edges firmly.
Squeeze harder, cut the filling to a level tablespoon, press the centre before pleating, and keep the water at a simmer so the surface barely trembles.