Make the filling

1. In a bowl, season the pork with the soy sauce and garlic and mix well. Set aside to develop flavors while you prep the other filling ingredients.
2. Wipe off any solid seasonings from the kimchi and finely dice.
3. In a separate bowl, mash the firm tofu with your hands until fine and uniform and wrap in a cheesecloth (muslin) or similar and squeeze to drain excess moisture.
4. In a small pot of boiling water, blanch the mung bean sprouts for 2 minutes. Drain and let cool in a sieve. Once cooled, cut into 1/8-inch (3 mm) pieces.
5. In a frying pan, heat the cooking oil over high heat. Add the seasoned pork and onions and stir-fry, breaking up the meat. While the meat is cooking, add the diced kimchi and stir-fry for 3 minutes. Scrape into a bowl to cool. Add the tofu, mung bean sprouts, egg, scallion, and salt and mix well until uniform.

Make the cho-ganjang

1. In a small bowl, stir together the soy sauce, 3 tablespoons water, the vinegar, and gochugaru and mix until uniform. Set aside in a saucer.

Assemble the dumplings

1. Place a mandu wrapper in the palm of your nondominant hand and lightly apply water to the outer edges. Place 1 tablespoon of filling in the center. Fold the mandu wrapper into a half- moon shape and press the center of the edge to fix, then press the outer edges firmly together to seal, leaving no air bubbles. Repeat for all remaining ingredients.
2. Set up a steamer and bring the water to a boil. Add the mandu to the steamer basket, set it over the boiling water, cover, and steam for about 10 minutes.
3. Plate the steamed dumplings on a large flat plate and serve with cho-ganjang on the side for dipping.

— Excerpted from The Korean Cookbook © 2023 by Junghyun Park and Jungyoon Choi. Photography © 2023 by Jinju Kang. Reproduced by permission of Phaidon. All rights reserved