The onion should be finely minced.
In a bowl, add the pork, miso, mirin, soy sauce, sugar, and potato starch, and mix well.
Divide up the mixture into 6 even-sized balls.
In another bowl, lightly mix together the pancake mix and olive oil, then continue mixing while adding water little by little.
If the mixture sticks to your fingers, add potato starch until it no longer does.
Divide this mixture up into 6 even-sized balls as well, then begin wrapping the pork balls with the pancake mix.
Once all 6 pork buns are wrapped, place them on a cooking sheet, then into a steamer.
If you do not have a steamer, add water in a frying pan, place the buns on a heat-safe plate that fit in the frying pan, then cover.
The buns are finished once they are fluffy.