Steps

1. Finely chop 1/2 onion after removing the core. Transfer the chopped onion to a bowl. (Key tip: The texture is up to your preference; both coarse and fine chopping result in delicious shumai.)
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2. Roughly chop 200g of pork shoulder for sauté into approximately 5mm cubes and lightly mince.
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3. In a large bowl, add 200g of ground pork and the minced pork shoulder from step 2. Add about 2 pinches of salt and knead firmly until sticky.
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4. To the same bowl, add [A]: 1.5 tbsp sugar, 2 tsp grated ginger, 1 tbsp sesame oil, 1 tbsp soy sauce, 2 tbsp oyster sauce, and about 3 pinches of pepper. Continue kneading firmly until the mixture turns pale and stringy. (Key tip: For meat dishes, 'kneading' is more important than 'mixing.' Kneading until it becomes stringy creates a smooth and delicious shumai.)
   🕒 06:55
5. Evenly coat the chopped onion from step 1 with 2 tbsp potato starch, gently mixing to coat each piece of onion. (Key tip: Coating with potato starch seals in the onion's juiciness. Avoid overmixing, as it can release moisture; mix just enough to coat.)
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6. Add the coated onion from step 5 to the meat mixture from step 4 and gently fold them together. Be careful not to overmix to prevent moisture from the onion.
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7. Let the meat mixture rest in the refrigerator for about 10 minutes to allow the flavors to meld. Chilling also makes it easier to handle.
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8. When separating about 20 wonton wrappers, rub them between both hands to peel them apart easily. (Key tip: Wonton wrappers are larger than shumai wrappers and are ideal for making meaty shumai.)
   🕒 11:17
9. Wrap the rested meat mixture with the wonton wrappers. Apply one portion of the meat mixture to a wrapper, flip it over, and shape it into a ball. Flatten the top and bottom, then gently shape a slight indentation with your thumb and index finger. (Key tip: Creating a slight indentation when shaping improves the appearance.)
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10. Bring water to a boil in a steamer. Once steaming, arrange the shumai and steam over medium heat for about 10 minutes. (Substitute: If you don't have a steamer, place a cloth in a frying pan, add 1cm of water, and steam the shumai placed on a heatproof plate with a lid. Alternatively, line the frying pan with chopped cabbage (to taste), add 1cm of water, place the shumai on top, cover, and steam.)
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11. While the shumai are steaming, shred cabbage (to taste).
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12. Arrange the steamed shumai on a plate, garnish with shredded cabbage and a little mustard, and serve. (Key tip: If steamed in a frying pan, the cabbage underneath can also be enjoyed. It's recommended to season it like a namul with sesame oil and soy sauce, or drizzle with ponzu.)
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