There are so many different variation from the original spelling in Japanese, but I believe the best one is "Konbucha", directly translated from the Japanese word 昆布茶.

Definition from Wikipedia: Kombucha is the Western name for sweetened tea or tisane that has been fermented by a macroscopic solid mass of microorganisms called a "kombucha colony," usually consisting principally of Acetobacter-species and yeast cultures.

Japanese people drink that as a kind of tea, but personally I don't really think it is a tea or a drink at all. I used Konbucha as a kind of herb, which usually I add when I was cooking a clear broth and sometimes you can add in konbucha powder when you are making seafood omelet. There are a few recipes that I have seen recently that made good use of Konbucha as a key ingredient. I think it brings out the savoriness out of the food, and is an alternative form of MSG (umami). One of the recipe that I can share.

Recipe

Crab Omelet with Konbucha (serves 4)

Ingredient:

1 can of crab meat (~60g)
grounded chicken meat(~120g)

Condiment A :

• cornstarch 2 teaspoon
• salt 1/4 teaspoon

Condiment B:

• sugar 2 teaspoon
• light soy sauce
  

6 Eggs
Soy Milk (80 ml)

Sauce:

• Konbucha 2 teaspoon
• light soy sauce
• cornstarch 2 teaspoon
• water 1 1/2 cup

Step 1:Mix crab meat, chicken meat and Condiment A in a bowl.

Step 2:Beat eggs and mix soy milk with Condiment B together, then mix all the food from Step 1, mix well.

Step 3:Heat a pan and add oil afterwards, add 1/4 of the mixture into the pan, flip after seeing the egg batter transform into semi-transparent state. Repeat the process to make 4 omeletes.

Step 4:After finishing, put the sauce to a boil in the pan and add in some black pepper when needed. Pour sauce over the completed crab omelete.

Step 5: Serve with rice/pasta.

Picture

One of the brand that I use, and it seem to be pretty prominent in Japense shop. This version of it doesn't add the plum flavor, and I like it because it is more managable.