Chop the fermented Kimchi and slice the onion. Put into a large mixing bowl. Add the flour and mix them for a minute. Add 2 cups (500ml) water and mix well.
Heat a frying pan to medium heat. Drop 2-3 drops oil in the pan. Using a scoop, place a good amount of the mixture in the pan, about 0.5 cm (1/4 inch) thick, flatten and try to smooth the edge. Cook for 3 minutes. Flip over, press lightly and cook 2 minutes more. The mixture will make about 6 large Kimchi patties.
Mix the ingredients for the dipping sauce. Serve with the dipping sauce.