Tentsuyu is Japan

Japan

Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

ese tempura

Tempura

], is a Japanese dish of seafood or vegetables that have been battered and deep fried.-Batter:A light batter is made of cold water and soft wheat flour . Eggs, baking soda or baking powder, starch, oil, and/or spices may also be added...

 dipping sauce.

The recipe

Recipe

A recipe is a set of instructions that describe how to prepare or make something, especially a culinary dish.-Components:Modern culinary recipes normally consist of several components*The name of the dish...

 for tentsuyu depends on the seasons and on the ingredients for which tentsuyu is being prepared. A general, all-purpose, tentsuyu might consists of three parts dashi

Dashi

Dashi is a class of soup and cooking stock, considered fundamental to Japanese cooking. In 1980, Shizuo Tsuji wrote: "Many substitutes for dashi are possible, but without dashi, dishes are merely à la japonaise and lack the authentic flavor." Dashi forms the base for miso soup, clear broth, noodle...

, one part mirin

Mirin

is an essential condiment used in Japanese cuisine, consisting of 40%–50% sugar. It is a kind of rice wine similar to sake, but with a lower alcohol content—14% instead of 20%. There are three general types. The first is hon mirin , which contains alcohol. The second is shio mirin, which contains...

, and one part soy sauce

Soy sauce

Soy sauce is a condiment produced by fermenting soybeans with Aspergillus oryzae or Aspergillus sojae molds, along with water and salt...

. For ingredients with strong odors or flavors, however, sake and sugar

Sugar

Sugar is a class of edible crystalline carbohydrates, mainly sucrose, lactose, and fructose, characterized by a sweet flavor.Sucrose in its refined form primarily comes from sugar cane and sugar beet...

 might be used instead of mirin, or more or less shoyu might be used.

Similar ingredients make up the simmering sauce for donburi

Donburi

Donburi is a Japanese "rice bowl dish" consisting of fish, meat, vegetables or other ingredients simmered together and served over rice. Donburi meals are served in oversized rice bowls also called donburi...

 and the broth for dishes like agedashi tofu

Agedashi tofu

Agedashi tofu is a Japanese way to serve hot tofu. Silken firm tofu, cut into cubes, is lightly dusted with potato starch or cornstarch and then deep fried until golden brown...

(deep-fried tofu in broth) and soba

Soba

is the Japanese name for buckwheat. It is synonymous with a type of thin noodle made from buckwheat flour, and in Japan can refer to any thin noodle . Soba noodles are served either chilled with a dipping sauce, or in hot broth as a noodle soup...

 (buckwheat noodles).

Tentsuyu in concentrated form is commonly sold in a small bottles in supermarkets and grocery stores throughout Japan—and also in Asia

Asia

Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...

n grocery stores in the US.

When used for tempura, tentsuyu is commonly served with grated daikon white radish

Daikon

Daikon , Raphanus sativus var. longipinnatus, also called White Radish, Japanese radish, Oriental radish, Chinese radish, lo bok and Mooli , is a mild flavoured, very large, white East Asian radish...

.