Jjin Mandu is a Korean version of potstickers and very similar to the Japanese gyoza. There are many variations of fillings which you can customise. You can add kimchi, cheese or even truffle if you are feeling extravagant.
In a big bowl, combine all the dumpling ingredients together, making sure that the chives, mushroom, garlic & spring onions are cut finely so as to achieve a solid mix. Season with salt and pepper.
Prepare a small bowl of water, to use as sealant. Wrap the dumplings up and use water to seal and 'pleat' the dumpling.
In a medium heat fry pan, put in some oil and start cooking each dumpling. When it colours, add about 3 tbsp of water and cover your pan. Let it steam through. Serve with dipping sauce.
Dipping Sauce: Combine soy, vinegar, sesame oil, shredded ginger, garlic and chopped chilli. Taste and season according to preference.
Notes
for kimchi mandu, replace soft tofu with kimchi
you can choose to boil or steam the mandu instead of pan-frying