Spread the sliced onion into a basket, and leave more than 20 minutes.
Remove the seed of umeboshi, and chop finely to make paste.
Serve the onion from Step 2 onto a plate, put the umeboshi from Step 3 around, and put the bonito flakes in the centre. Pour the noodle dipping sauce and done.
Story Behind this Recipe
The way to reduce the pungent taste is by cutting at right angles and contact with air. I tried it and it is very effective.
By cutting the onion at right angles, it kills the cell and put the pungent component in front. And by spreading in basket on contacting with air blows the pungent taste away. Also the sourness of umeboshi helps to shade off the pungent taste.