Umeboshi (Pickled plums)

4 kg fresh ume 
500-600 gm salt
1½ C rice vinegar
(¼ C mirin)

Wash the plums thoroughly and remove the stems. Cull out any that aren't good. Dry them completely.

Mix the salt and vinegar. Put a big, new, plastic bag in a big bowl and add the ume carefully so you don't squish any. Pour in the salt and vinegar. Mix about gently so all the ume are covered with the liquid. Tie the bag shut with a minimum of air inside. 

Place the big bowl in an out-of-the-way place and put something flat on top, then a heavy weight on top of that to push the flat lid down. (I used an unbreakable plate with a dumbbell on top. Canned food works pretty well, too.)

Leave it to soak for a month or so until red shiso (Perilla leaves) come into season. 

(Optional:  Dry them for a day or two in the sun. Save the soaking liquid.)

2-3 big bundles of red shiso leaves

Remove the leaves from the stems, wash the shiso leaves, and dry them thoroughly. 

Open up your ume and take some of the liquid out and put it in a big bowl. Add shiso leaves and squeeze them together. Repeat this until your shiso is all used.

A few months after making.

Layer the ume with shiso leaves inside a big, clean, dry mason jar. (To be sure it's really clean, rinse it with a little vodka.) Then pour on the liquid. Put in an out-of-the-way place to store. They will be ready to eat in 2-3 months. These keep indefinitely, and they improve with age. You may want to turn them from time to time so all the ume get evenly colored.

Before they are ready to be served, dry them in the sun for a day.