Cut the cabbage into 2 x 5 cm easy-to-eat pieces.
Tear the umeboshi with your hands. Thinly slice the red pepper. Julienne the ginger.
Put everything in a plastic bag, other than the sesame seeds, and massage it.
Let it set in the fridge for 20 minutes.
When you've placed it on a plate, add the sesame seeds to your liking and drizzle some lemon juice (not listed) on top and it will become even more aromatic.
Story Behind this Recipe
I can't find good quality pickles where I live.
To improve the aroma, I recommend a squirt of fresh lemon (yuzu or kabozu works too). If you do that, you can decrease the amount of salt, and it's still delicious. You can store it in the fridge for 3 days.