The following essay is what I wrote as an assignment of an English school AEON.

Topic: Japanese food
Style: Casual

If we ask some foreigners about their favorite Japanese food, answers might be almost always the same: sushi, tempura, sashimi, and so on. I think the most important thing in Japanese food is not a specific type of dish, but an element or ingredient, namely, dashi. I do not think there is an exact corresponding word in English, but soup or soup stock could be the one. As for the types of tastes of human, there were only four in western countries, namely sweetness, sourness, saltiness, and bitterness. In Japan, we had one more taste called umami. Though the fifth taste was just empirically known, Kikunae Ikeda found that L-monosodium glutamate could make us sense umami in 1907. He derived the chemical by boiling dried kelp, which is one of the most popular ingredients to get good dashi in Japan. Most western scientists did not approve the new taste, but it was proven that there are receptors of umami on our tongues in 2000. Dashi means soup that can provide any dishes with umami. For most Japanese dishes, we use some dashi in them. The most typical sauce shoyu or soy source contains a lot of umami in it such as amino acid, glutamic acid, and asparagine acid. Now umami is translated into English as savory.
Except for dried kelp, we use katsuobushi, dried bonito, niboshi or iriko, dried small sardine, and also dried shiitake mushroom, and so on. Combinations of dried kelp and dried bonito are the most important skill for all Japanese dishes’ chefs. One good thing about these two ingredients is that they are well prepared for daily usage and we can easily use them even at home. On the contrast, in French dishes, chefs take some burdensome steps to get Bouillon, or broth.
Do not forget one more important material: water. Some western chefs tried to use dried kelp and dried bonito in their countries, but because of the different quality of water, they could not get good dashi. I heard that some famous Japanese chefs brought a big bottle of Japanese water with them when they were asked to cook in foreign countries.
I show you a good example of Japanese dishes that utilize dashi: Dashi maki tamago, or Japanese style rolled omelet with dashi. It is a very simple dish, just bake egg with dashi mixed, but it is very tough to get a good figure. We use a special small square pan just for this dish.
At last, one thing I hate is that many Japanese house wives use instant powder type dashi that uses MSG for their daily dishes. I never choose convenience over getting good dashi.