Place the sliced chinese leaf cabbage in a bowl. Sprinkle over 1 tbsp salt and mix well. Leave to sit for an hour, until the cabbage starts to wilt.
Meanwhile, mix all of the ingredients for the burgers apart from the oil together, reserving some of the sesame seeds for garnishing. Divide the mixture into 4 and shape into patties. Place on a tray in the fridge to firm up for around an hour.
Rinse the cabbage under cold water to get rid of the salt. Combine the other ingredients for the kimchi and mix into the cabbage.
Place a large frying pan over a medium heat with the oil and fry the burgers for 4-5 minutes on each side, until just cooked through.
Place a burger on the bottom half of each bun. Top with kimchi and sesame seeds, then the bun top.