Cup of Yum
1. Gather all the ingredients. Sterilize a jar or pour hot water and wipe the jar with high % alcohol (shochu or vodka).
2. Peel 7 oz young ginger with a sharp knife (or the back of the knife) or a spoon. The skin is very thin, so you can easily remove the brown spots.
3. Using the knife, thinly slice the ginger lengthwise into thin slabs. Stack several slabs and cut into julienned strips.
4. Bring a medium pot of water to a boil over medium-high heat. Add the ginger strips and blanch for 2 to 3 minutes.
5. Drain the ginger well in a fine-mesh sieve and let cool over a large flat surface (I used a bonzaru, Japanese bamboo sieve). Alternatively, wrap in a clean kitchen towel, and gently squeeze to remove excess liquid. The ginger cooking liquid can be enjoyed as ginger tea or shoga-yu (生姜湯).
6. Once cool completely, add the ginger into small jars or one big jar/container.
7. Add ¼ cup ume plum vinegar. Here, I show two variations: two dark red and two light red in color. To make lighter red, you only add a small amount of ume plum vinegar, almost no excess liquid in the jar.
8. Mix well and close the lid. Store the jar in the refrigerator overnight and up to several days.

To Store

1. You can keep the red pickled ginger in the refrigerator for up to a year. Always use a clean utensil to pick the ginger from the jar before serving.